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    <filerInfo>
      
      <filer>
        <issuerCredentials>
          <cik>0000355437</cik>
          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
      </filer>
      
      
      <seriesClassInfo>
        <seriesId>S000055975</seriesId>
        <classId>C000176269</classId>
      </seriesClassInfo>
      
      
    </filerInfo>
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      <regFileNumber>811-03258</regFileNumber>
      <regCik>0000355437</regCik>
      <regLei>549300XGRTBJCE41BD26</regLei>
      <regStreet1>6300 BEE CAVE ROAD</regStreet1>
      <regStreet2>BUILDING ONE</regStreet2>
      <regCity>AUSTIN</regCity>
      <regStateConditional regCountry="US" regState="US-TX"/>
      <regZipOrPostalCode>78746</regZipOrPostalCode>
      <regPhone>512-306-7400</regPhone>
      <seriesName>Global Small Company Portfolio</seriesName>
      <seriesId>S000055975</seriesId>
      <seriesLei>549300LV5BCK35AQXF59</seriesLei>
      <repPdEnd>2026-10-31</repPdEnd>
      <repPdDate>2026-04-30</repPdDate>
      <isFinalFiling>N</isFinalFiling>
    </genInfo>
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      <totLiabs>48295.27</totLiabs>
      <netAssets>149970199.90</netAssets>
      <assetsAttrMiscSec>0.00000000</assetsAttrMiscSec>
      <assetsInvested>0.00000000</assetsInvested>
      <amtPayOneYrBanksBorr>0.00000000</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0.00000000</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0.00000000</amtPayOneYrOthAffil>
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      <amtPayAftOneYrBanksBorr>0.00000000</amtPayAftOneYrBanksBorr>
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      <amtPayAftOneYrOther>0.00000000</amtPayAftOneYrOther>
      <delayDeliv>0.00000000</delayDeliv>
      <standByCommit>0.00000000</standByCommit>
      <liquidPref>0.00000000</liquidPref>
      <cshNotRptdInCorD>55962.19000000</cshNotRptdInCorD>
      <isNonCashCollateral>N</isNonCashCollateral>
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            <mon2 netRealizedGain="22989.90000000" netUnrealizedAppr="0.00000000"/>
            <mon3 netRealizedGain="0.00000000" netUnrealizedAppr="0.00000000"/>
            <futureCategory>
              <instrMon1 netRealizedGain="0.00000000" netUnrealizedAppr="0.00000000"/>
              <instrMon2 netRealizedGain="22989.90000000" netUnrealizedAppr="0.00000000"/>
              <instrMon3 netRealizedGain="0.00000000" netUnrealizedAppr="0.00000000"/>
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        <othMon2 netRealizedGain="-10479.88000000" netUnrealizedAppr="-4751161.97000000"/>
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      <mon2Flow redemption="1129371.14000000" reinvestment="0.00000000" sales="7802624.09000000"/>
      <mon3Flow redemption="896993.78000000" reinvestment="0.00000000" sales="546894.05000000"/>
      
      
    </fundInfo>
    <invstOrSecs>
      <invstOrSec>
        <name>DFA US Small Cap Portfolio</name>
        <lei>54930002ZNZ4W0THTP70</lei>
        <title>U.S. Small Cap Portfolio</title>
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        <identifiers>
          <isin value="US2332038437"/>
        </identifiers>
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        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>92469025.89000000</valUSD>
        <pctVal>61.65826674343</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>549300CBGM4U9R4DEL16</lei>
        <title>THE ASIA PACIFIC SMALL COMPANY SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAH_MASTER"/>
        </identifiers>
        <balance>55005.23000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3955426.10000000</valUSD>
        <pctVal>2.637474713401</pctVal>
        <payoffProfile>Long</payoffProfile>
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        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>54930006OMTUF18TBS36</lei>
        <title>THE CANADIAN SMALL COMPANY SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAE_MASTER"/>
        </identifiers>
        <balance>159517.88000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5769761.82000000</valUSD>
        <pctVal>3.847272207310</pctVal>
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        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>549300XCLYJKZX2XQ177</lei>
        <title>THE JAPANESE SMALL COMPANY SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAJ_MASTER"/>
        </identifiers>
        <balance>260251.61000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8611725.83000000</valUSD>
        <pctVal>5.742291359044</pctVal>
        <payoffProfile>Long</payoffProfile>
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        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>549300FCYEDRJO2L0O02</lei>
        <title>THE UNITED KINGDOM SMALL COMPANY SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAI_MASTER"/>
        </identifiers>
        <balance>38285.87000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4105776.20000000</valUSD>
        <pctVal>2.737728030460</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
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      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>5493003AI5702G3MYM49</lei>
        <title>THE EMERGING MARKETS SMALL CAP SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAL_MASTER"/>
        </identifiers>
        <balance>140872.11000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>19014916.98000000</valUSD>
        <pctVal>12.67913024899</pctVal>
        <payoffProfile>Long</payoffProfile>
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        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Dimensional Fund Advisors</name>
        <lei>549300TTGDINCXXSVF04</lei>
        <title>THE CONTINENTAL SMALL COMPANY SERIES</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="DFAF_MASTER"/>
        </identifiers>
        <balance>87058.66000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15998770.37000000</valUSD>
        <pctVal>10.66796628974</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>N/A</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-05-19</ncom:dateSigned>
      <ncom:nameOfApplicant>DFA INVESTMENT DIMENSIONS GROUP INC</ncom:nameOfApplicant>
      <ncom:signature>Randy Olson</ncom:signature>
      <ncom:signerName>Randy Olson</ncom:signerName>
      <ncom:title>Vice President</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
