<SUBMISSION>
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<PERIOD>20031125
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<OWNER-DATA>
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<CIK>0001215329
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<FILM-NUMBER>031023353
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<BUSINESS-ADDRESS>
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<CITY>LONG GROVE
<STATE>IL
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<PHONE>8474656000
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<ISSUER>
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<CONFORMED-NAME>CDW CORP
<CIK>0000899171
<ASSIGNED-SIC>5961
<IRS-NUMBER>363310735
<STATE-OF-INCORPORATION>IL
<FISCAL-YEAR-END>1231
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<BUSINESS-ADDRESS>
<STREET1>200 N MILWAUKEE AVE
<CITY>VERNON HILLS
<STATE>IL
<ZIP>60061
<PHONE>8474656000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>200 N MILWAUKEE AVE
<CITY>VERNON HILLS
<STATE>IL
<ZIP>60061
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<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CDW COMPUTER CENTERS INC
<DATE-CHANGED>19930322
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<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

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    <issuer>
        <issuerCik>0000899171</issuerCik>
        <issuerName>CDW CORP</issuerName>
        <issuerTradingSymbol>CDWC</issuerTradingSymbol></issuer><reportingOwner>
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            <rptOwnerName>ECKROTE DOUGLAS E</rptOwnerName>
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            <rptOwnerStreet1>200 N MILWAUKEE AVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>VERNON HILLS</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60061</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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