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        <classId>C000170210</classId>
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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>DFA Diversified Fixed Income Portfolio</seriesName>
      <seriesId>S000054156</seriesId>
      <seriesLei>549300VV3QSNEWJBLF55</seriesLei>
      <repPdEnd>2026-10-31</repPdEnd>
      <repPdDate>2026-07-31</repPdDate>
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      <totLiabs>244639.04</totLiabs>
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      <assetsInvested>0.00000000</assetsInvested>
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        <fairValLevel>1</fairValLevel>
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      </invstOrSec>
      <invstOrSec>
        <name>DFA Intermediate Government Fixed Income Portfolio</name>
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        <invCountry>US</invCountry>
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        <fairValLevel>1</fairValLevel>
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        <name>State Street Global Advisors</name>
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        <assetCat>STIV</assetCat>
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        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
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          <isLoanByFund>N</isLoanByFund>
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      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
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        <fairValLevel>2</fairValLevel>
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          <couponKind>Fixed</couponKind>
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          <isCashCollateral>N</isCashCollateral>
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        <name>United States Treasury</name>
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        <curCd>USD</curCd>
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        <invCountry>US</invCountry>
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        <fairValLevel>2</fairValLevel>
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      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Notes</title>
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        <invCountry>US</invCountry>
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        <fairValLevel>2</fairValLevel>
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        <fairValLevel>2</fairValLevel>
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        <fairValLevel>2</fairValLevel>
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        <name>United States Treasury</name>
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        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>33311630.26000000</valUSD>
        <pctVal>2.001416902745</pctVal>
        <payoffProfile>Long</payoffProfile>
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        <invCountry>US</invCountry>
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        <fairValLevel>2</fairValLevel>
        <debtSec>
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          <couponKind>Fixed</couponKind>
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          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
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        <securityLending>
          <isCashCollateral>N</isCashCollateral>
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          <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"/>
      <explntrNote note="For purposes of Item C.6 identifying restricted securities,  a security that is subject to Rule 144A under the Securities Act of 1933, as amended, is identified as a restricted security only if the fund cannot sell the security to qualified institutional buyers at the report date due to the restrictions under Rule 144A." noteItem="C.6"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-08-31</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>
  <documents>XXXX</documents>
</edgarSubmission>
