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        <name>Calvert International Responsible Index Fund</name>
        <lei>5493002R7L7YSTUULM88</lei>
        <title>Calvert International Responsible Index Fund</title>
        <cusip>13161Y848</cusip>
        <identifiers>
          <isin value="US13161Y8488"/>
        </identifiers>
        <balance>1125781.21000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>39559951.54000000</valUSD>
        <pctVal>11.04739852525</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>Calvert International Equity Fund</name>
        <lei>549300DYXGATLWKZ1990</lei>
        <title>Calvert International Equity Fund</title>
        <cusip>131649741</cusip>
        <identifiers>
          <isin value="US1316497411"/>
        </identifiers>
        <balance>1054429.30000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>28575033.92000000</valUSD>
        <pctVal>7.979781958723</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>Calvert Short-Duration Income Fund</name>
        <lei>549300KRHGOWQEB8SR45</lei>
        <title>Calvert Short-Duration Income Fund</title>
        <cusip>131582264</cusip>
        <identifiers>
          <isin value="US1315822643"/>
        </identifiers>
        <balance>4763.08000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>75637.74000000</valUSD>
        <pctVal>0.021122378183</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>2025-07-25</ncom:dateSigned>
      <ncom:nameOfApplicant>Calvert Social Investment Fund</ncom:nameOfApplicant>
      <ncom:signature>James Kirchner</ncom:signature>
      <ncom:signerName>James Kirchner</ncom:signerName>
      <ncom:title>Treasurer</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
