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<ISSUER>
<COMPANY-DATA>
<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
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CDW COMPUTER CENTERS INC
<DATE-CHANGED>19930322
</FORMER-COMPANY>
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<REPORTING-OWNER>
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<CONFORMED-NAME>KRASNY MICHARLE P
<CIK>0000942499
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<FILING-VALUES>
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<ACT>34
<FILE-NUMBER>000-21796
<FILM-NUMBER>03805130
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<MAIL-ADDRESS>
<STREET1>812 SKOKIE BLVD
<CITY>NORTHBROOK
<STATE>IL
<ZIP>60062
</MAIL-ADDRESS>
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<?xml version="1.0"?>
<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>KRASNY MICHARLE P</rptOwnerName>
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        <reportingOwnerAddress>
            <rptOwnerStreet1>200 NORTH MILWAUKEE AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>VERNON HILLS</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60061</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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