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      <filer>
        <issuerCredentials>
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          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
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      <seriesClassInfo>
        <seriesId>S000050936</seriesId>
        <classId>C000160536</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>DIMENSIONAL 2020 TARGET DATE RETIREMENT INCOME FUND</seriesName>
      <seriesId>S000050936</seriesId>
      <seriesLei>549300OERBTGUJDCET21</seriesLei>
      <repPdEnd>2026-10-31</repPdEnd>
      <repPdDate>2026-04-30</repPdDate>
      <isFinalFiling>N</isFinalFiling>
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      <totLiabs>289206.68</totLiabs>
      <netAssets>56413077.63</netAssets>
      <assetsAttrMiscSec>0.00000000</assetsAttrMiscSec>
      <assetsInvested>0.00000000</assetsInvested>
      <amtPayOneYrBanksBorr>281000.00000000</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0.00000000</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0.00000000</amtPayOneYrOthAffil>
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      <amtPayAftOneYrOther>0.00000000</amtPayAftOneYrOther>
      <delayDeliv>0.00000000</delayDeliv>
      <standByCommit>0.00000000</standByCommit>
      <liquidPref>0.00000000</liquidPref>
      <cshNotRptdInCorD>33.48000000</cshNotRptdInCorD>
      <isNonCashCollateral>N</isNonCashCollateral>
      <returnInfo>
        <monthlyTotReturns>
          <monthlyTotReturn classId="C000160536" rtn1="1.68000000" rtn2="-3.00000000" rtn3="3.14000000"/>
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        <othMon3 netRealizedGain="167670.72000000" netUnrealizedAppr="1537610.20000000"/>
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      <mon2Flow redemption="1914062.34000000" reinvestment="24297.75000000" sales="450881.63000000"/>
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    </fundInfo>
    <invstOrSecs>
      <invstOrSec>
        <name>DFA Large Cap International Portfolio</name>
        <lei>549300YQLH5F7D7ZFY39</lei>
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        <identifiers>
          <isin value="US2332038684"/>
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        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
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          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>DFA US Large Company Portfolio</name>
        <lei>549300FK54SMFUX28R78</lei>
        <title>U.S. Large Company Portfolio</title>
        <cusip>25434D823</cusip>
        <identifiers>
          <isin value="US25434D8231"/>
        </identifiers>
        <balance>106240.01000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5083584.29000000</valUSD>
        <pctVal>9.011357833270</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>International Core Equity 2 Portfolio</name>
        <lei>5493006PNAH8EX4MI695</lei>
        <title>International Core Equity 2 Portfolio</title>
        <cusip>233203371</cusip>
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          <isin value="US2332033719"/>
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        <issuerCat>RF</issuerCat>
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        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>DFA US Core Equity 1 Portfolio</name>
        <lei>549300HFCYX77UDJN369</lei>
        <title>U.S. Core Equity 1 Portfolio</title>
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          <isin value="US2332034139"/>
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        <payoffProfile>Long</payoffProfile>
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        <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>DFA Inflation Protected Securities Portfolio</name>
        <lei>549300TG645KDIW1X492</lei>
        <title>DFA Inflation-Protected Securities Portfolio</title>
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        <identifiers>
          <isin value="US2332033552"/>
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        <balance>3288411.91000000</balance>
        <units>NS</units>
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        <payoffProfile>Long</payoffProfile>
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        <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>Emerging Markets Core Equity 2 Portfolio</name>
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        <title>Emerging Markets Core Equity 2 Portfolio</title>
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        <units>NS</units>
        <curCd>USD</curCd>
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        <pctVal>2.539679397385</pctVal>
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        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>DFA LTIP Portfolio</name>
        <lei>5493002LL7DG39YNJG30</lei>
        <title>DFA LTIP Portfolio</title>
        <cusip>25239Y873</cusip>
        <identifiers>
          <isin value="US25239Y8738"/>
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        <balance>1009938.34000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5140586.16000000</valUSD>
        <pctVal>9.112401549363</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>
    </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>
