<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:77d9b4f3-1e9b-4350-83ea-b0254082bfc0,g:7375f414-00f3-4163-ad72-3e2221a33bd9-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_ck0001027596_C000201595Member_label_en-US" xlink:label="lab_ck0001027596_C000201595Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund Investor Class</link:label>
    <link:label id="lab_ck0001027596_C000201595Member_documentation_en-US" xlink:label="lab_ck0001027596_C000201595Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund Investor Class, C000201595</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000201595Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000201595Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000201595Member" xlink:to="lab_ck0001027596_C000201595Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI EAFE Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI EAFE Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIEAFEIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_S000044708Member_label_en-US" xlink:label="lab_ck0001027596_S000044708Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund</link:label>
    <link:label id="lab_ck0001027596_S000044708Member_documentation_en-US" xlink:label="lab_ck0001027596_S000044708Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund, S000044708</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_S000044708Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_S000044708Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_S000044708Member" xlink:to="lab_ck0001027596_S000044708Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MidCapCompanyRiskMember_label_en-US" xlink:label="lab_ck0001027596_MidCapCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mid Cap Company Risk Member</link:label>
    <link:label id="lab_ck0001027596_MidCapCompanyRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_MidCapCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Mid Cap Company Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MidCapCompanyRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MidCapCompanyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MidCapCompanyRiskMember" xlink:to="lab_ck0001027596_MidCapCompanyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_EmergingMarketsRiskMember_label_en-US" xlink:label="lab_ck0001027596_EmergingMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk Member</link:label>
    <link:label id="lab_ck0001027596_EmergingMarketsRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_EmergingMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Emerging Markets Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_EmergingMarketsRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_EmergingMarketsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_EmergingMarketsRiskMember" xlink:to="lab_ck0001027596_EmergingMarketsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 2000&#174; Total Return Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 2000&#174; Total Return Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0001027596_Russell2000TotalReturnIndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_CurrencyRiskMember_label_en-US" xlink:label="lab_ck0001027596_CurrencyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Currency Risk Member</link:label>
    <link:label id="lab_ck0001027596_CurrencyRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_CurrencyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Currency Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_CurrencyRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_CurrencyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_CurrencyRiskMember" xlink:to="lab_ck0001027596_CurrencyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_ForeignSecuritiesRiskMember_label_en-US" xlink:label="lab_ck0001027596_ForeignSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Securities Risk Member</link:label>
    <link:label id="lab_ck0001027596_ForeignSecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ForeignSecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Foreign Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_ForeignSecuritiesRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_ForeignSecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_ForeignSecuritiesRiskMember" xlink:to="lab_ck0001027596_ForeignSecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_ValueStyleInvestingRiskMember_label_en-US" xlink:label="lab_ck0001027596_ValueStyleInvestingRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Value Style Investing Risk Member</link:label>
    <link:label id="lab_ck0001027596_ValueStyleInvestingRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ValueStyleInvestingRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Value Style Investing Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_ValueStyleInvestingRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_ValueStyleInvestingRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_ValueStyleInvestingRiskMember" xlink:to="lab_ck0001027596_ValueStyleInvestingRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell Midcap&#174; Value Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell Midcap&#174; Value Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_RussellMidcapRValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember_label_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk, Industrials Sector Risk Member</link:label>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk, Industrials Sector Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember" xlink:to="lab_ck0001027596_SectorEmphasisRiskIndustrialsSectorRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000138964Member_label_en-US" xlink:label="lab_ck0001027596_C000138964Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund Institutional Class</link:label>
    <link:label id="lab_ck0001027596_C000138964Member_documentation_en-US" xlink:label="lab_ck0001027596_C000138964Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund Institutional Class, C000138964</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000138964Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000138964Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000138964Member" xlink:to="lab_ck0001027596_C000138964Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_EquitySecuritiesRiskMember_label_en-US" xlink:label="lab_ck0001027596_EquitySecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities Risk Member</link:label>
    <link:label id="lab_ck0001027596_EquitySecuritiesRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_EquitySecuritiesRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Securities Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_EquitySecuritiesRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_EquitySecuritiesRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_EquitySecuritiesRiskMember" xlink:to="lab_ck0001027596_EquitySecuritiesRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_EconomicAndMarketRiskMember_label_en-US" xlink:label="lab_ck0001027596_EconomicAndMarketRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Economic And Market Risk Member</link:label>
    <link:label id="lab_ck0001027596_EconomicAndMarketRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_EconomicAndMarketRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Economic And Market Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_EconomicAndMarketRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_EconomicAndMarketRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_EconomicAndMarketRiskMember" xlink:to="lab_ck0001027596_EconomicAndMarketRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000138962Member_label_en-US" xlink:label="lab_ck0001027596_C000138962Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund Institutional Class</link:label>
    <link:label id="lab_ck0001027596_C000138962Member_documentation_en-US" xlink:label="lab_ck0001027596_C000138962Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund Institutional Class, C000138962</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000138962Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000138962Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000138962Member" xlink:to="lab_ck0001027596_C000138962Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA IMI Index Net (USD)&#8232;(reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA IMI Index Net (USD)&#8232;(reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0001027596_MSCIWORLDExUSAIMIIndexNetUSDReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_LimitedPartnershipAndMLPRiskMember_label_en-US" xlink:label="lab_ck0001027596_LimitedPartnershipAndMLPRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Limited Partnership And MLP Risk Member</link:label>
    <link:label id="lab_ck0001027596_LimitedPartnershipAndMLPRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_LimitedPartnershipAndMLPRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Limited Partnership And MLP Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_LimitedPartnershipAndMLPRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_LimitedPartnershipAndMLPRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_LimitedPartnershipAndMLPRiskMember" xlink:to="lab_ck0001027596_LimitedPartnershipAndMLPRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_S000072390Member_label_en-US" xlink:label="lab_ck0001027596_S000072390Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Value Fund</link:label>
    <link:label id="lab_ck0001027596_S000072390Member_documentation_en-US" xlink:label="lab_ck0001027596_S000072390Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Value Fund</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_S000072390Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_S000072390Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_S000072390Member" xlink:to="lab_ck0001027596_S000072390Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_RealEstateInvestmentTrustREITRiskMember_label_en-US" xlink:label="lab_ck0001027596_RealEstateInvestmentTrustREITRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trust (REIT) Risk Member</link:label>
    <link:label id="lab_ck0001027596_RealEstateInvestmentTrustREITRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_RealEstateInvestmentTrustREITRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trust (REIT) Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_RealEstateInvestmentTrustREITRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_RealEstateInvestmentTrustREITRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_RealEstateInvestmentTrustREITRiskMember" xlink:to="lab_ck0001027596_RealEstateInvestmentTrustREITRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 3000&#174; Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 3000&#174; Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0001027596_Russell3000IndexReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_DepositaryReceiptRiskMember_label_en-US" xlink:label="lab_ck0001027596_DepositaryReceiptRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depositary Receipt Risk Member</link:label>
    <link:label id="lab_ck0001027596_DepositaryReceiptRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_DepositaryReceiptRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Depositary Receipt Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_DepositaryReceiptRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_DepositaryReceiptRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_DepositaryReceiptRiskMember" xlink:to="lab_ck0001027596_DepositaryReceiptRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI EAFE Value Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI EAFE Value Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIEAFEValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember_label_en-US" xlink:label="lab_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trust (REIT) And Foreign Real Estate Company Risk Member</link:label>
    <link:label id="lab_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Real Estate Investment Trust (REIT) And Foreign Real Estate Company Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember" xlink:to="lab_ck0001027596_RealEstateInvestmentTrustREITAndForeignRealEstateCompanyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Value (Net USD) (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Value (Net USD) (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIEmergingMarketsValueNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000228587Member_label_en-US" xlink:label="lab_ck0001027596_C000228587Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Value Class Instutitional Class</link:label>
    <link:label id="lab_ck0001027596_C000228587Member_documentation_en-US" xlink:label="lab_ck0001027596_C000228587Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Value Class Instutitional Class, C000228587</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000228587Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000228587Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000228587Member" xlink:to="lab_ck0001027596_C000228587Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember_label_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk, Financial Services Sector Risk Member</link:label>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk, Financial Services Sector Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember" xlink:to="lab_ck0001027596_SectorEmphasisRiskFinancialServicesSectorRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000168874Member_label_en-US" xlink:label="lab_ck0001027596_C000168874Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund Institutional Class</link:label>
    <link:label id="lab_ck0001027596_C000168874Member_documentation_en-US" xlink:label="lab_ck0001027596_C000168874Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund Institutional Class, C000168874</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000168874Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000168874Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000168874Member" xlink:to="lab_ck0001027596_C000168874Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA Small Cap Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA Small Cap Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIWORLDexUSASmallCapIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_S000053713Member_label_en-US" xlink:label="lab_ck0001027596_S000053713Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund</link:label>
    <link:label id="lab_ck0001027596_S000053713Member_documentation_en-US" xlink:label="lab_ck0001027596_S000053713Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund Series, S000053713</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_S000053713Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_S000053713Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_S000053713Member" xlink:to="lab_ck0001027596_S000053713Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000138961Member_label_en-US" xlink:label="lab_ck0001027596_C000138961Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund Investor Class</link:label>
    <link:label id="lab_ck0001027596_C000138961Member_documentation_en-US" xlink:label="lab_ck0001027596_C000138961Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund Investor Class, C000138961</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000138961Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000138961Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000138961Member" xlink:to="lab_ck0001027596_C000138961Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 1000 Total Return (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 1000 Total Return (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:to="lab_ck0001027596_Russell1000TotalReturnReflectsNoDeductionForFeesExpensesOrTaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA Small Cap Value Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI WORLD ex USA Small Cap Value Index Net (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIWORLDexUSASmallCapValueIndexNetreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000201596Member_label_en-US" xlink:label="lab_ck0001027596_C000201596Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund Institutional Class</link:label>
    <link:label id="lab_ck0001027596_C000201596Member_documentation_en-US" xlink:label="lab_ck0001027596_C000201596Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund Institutional Class, C000201596</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000201596Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000201596Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000201596Member" xlink:to="lab_ck0001027596_C000201596Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskMember_label_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk Member</link:label>
    <link:label id="lab_ck0001027596_SectorEmphasisRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_SectorEmphasisRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sector Emphasis Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_SectorEmphasisRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_SectorEmphasisRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_SectorEmphasisRiskMember" xlink:to="lab_ck0001027596_SectorEmphasisRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_FrontierMarketsRiskMember_label_en-US" xlink:label="lab_ck0001027596_FrontierMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Frontier Markets Risk Member</link:label>
    <link:label id="lab_ck0001027596_FrontierMarketsRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_FrontierMarketsRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Frontier Markets Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_FrontierMarketsRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_FrontierMarketsRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_FrontierMarketsRiskMember" xlink:to="lab_ck0001027596_FrontierMarketsRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000228588Member_label_en-US" xlink:label="lab_ck0001027596_C000228588Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Value Fund Investor Class</link:label>
    <link:label id="lab_ck0001027596_C000228588Member_documentation_en-US" xlink:label="lab_ck0001027596_C000228588Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Value Fund Investor Class, C000228588</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000228588Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000228588Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000228588Member" xlink:to="lab_ck0001027596_C000228588Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000168873Member_label_en-US" xlink:label="lab_ck0001027596_C000168873Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund Investor Class</link:label>
    <link:label id="lab_ck0001027596_C000168873Member_documentation_en-US" xlink:label="lab_ck0001027596_C000168873Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Small Cap Value Fund Investor Class, C000168873</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000168873Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000168873Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000168873Member" xlink:to="lab_ck0001027596_C000168873Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_ManagementRiskMember_label_en-US" xlink:label="lab_ck0001027596_ManagementRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Management Risk Member</link:label>
    <link:label id="lab_ck0001027596_ManagementRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_ManagementRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Management Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_ManagementRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_ManagementRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_ManagementRiskMember" xlink:to="lab_ck0001027596_ManagementRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_S000044707Member_label_en-US" xlink:label="lab_ck0001027596_S000044707Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund</link:label>
    <link:label id="lab_ck0001027596_S000044707Member_documentation_en-US" xlink:label="lab_ck0001027596_S000044707Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Mid Cap Value Fund Series, S000044707</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_S000044707Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_S000044707Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_S000044707Member" xlink:to="lab_ck0001027596_S000044707Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_SmallCapCompanyRiskMember_label_en-US" xlink:label="lab_ck0001027596_SmallCapCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Small Cap Company Risk Member</link:label>
    <link:label id="lab_ck0001027596_SmallCapCompanyRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_SmallCapCompanyRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Small Cap Company Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_SmallCapCompanyRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_SmallCapCompanyRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_SmallCapCompanyRiskMember" xlink:to="lab_ck0001027596_SmallCapCompanyRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_S000062254Member_label_en-US" xlink:label="lab_ck0001027596_S000062254Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund</link:label>
    <link:label id="lab_ck0001027596_S000062254Member_documentation_en-US" xlink:label="lab_ck0001027596_S000062254Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena International Small Cap Value Fund Series, S000062254</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_S000062254Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_S000062254Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_S000062254Member" xlink:to="lab_ck0001027596_S000062254Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Russell 2000&#174; Value Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Russell 2000&#174; Value Index (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_Russell2000RValueIndexreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_LiquidityRiskMember_label_en-US" xlink:label="lab_ck0001027596_LiquidityRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liquidity Risk Member</link:label>
    <link:label id="lab_ck0001027596_LiquidityRiskMember_documentation_en-US" xlink:label="lab_ck0001027596_LiquidityRiskMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Liquidity Risk Member</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_LiquidityRiskMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_LiquidityRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_LiquidityRiskMember" xlink:to="lab_ck0001027596_LiquidityRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_C000138963Member_label_en-US" xlink:label="lab_ck0001027596_C000138963Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund Investor Class</link:label>
    <link:label id="lab_ck0001027596_C000138963Member_documentation_en-US" xlink:label="lab_ck0001027596_C000138963Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pzena Emerging Markets Value Fund Investor Class, C000138963</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_C000138963Member" xlink:href="ck0001027596-20260626.xsd#ck0001027596_C000138963Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_C000138963Member" xlink:to="lab_ck0001027596_C000138963Member" xlink:type="arc" order="1"/>
    <link:label id="lab_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember_label_en-US" xlink:label="lab_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Index (Net USD) (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:label id="lab_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember_documentation_en-US" xlink:label="lab_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">MSCI Emerging Markets Index (Net USD) (reflects no deduction for fees, expenses or taxes)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:href="ck0001027596-20260626.xsd#ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:to="lab_ck0001027596_MSCIEmergingMarketsIndexNetUSDreflectsnodeductionforfeesexpensesortaxesIndexMember" xlink:type="arc" order="1"/>
  </link:labelLink>
</link:linkbase>
