<SUBMISSION>
<ACCESSION-NUMBER>0001144215-08-000058
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20080801
<FILING-DATE>20080805
<DATE-OF-FILING-DATE-CHANGE>20080805
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>ACUITY BRANDS INC
<CIK>0001144215
<ASSIGNED-SIC>5160
<IRS-NUMBER>582632672
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>0831
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>1170 PEACHTREE STREET, NE
<STREET2>SUITE 2400
<CITY>ATLANTA
<STATE>GA
<ZIP>30309-7676
<PHONE>404-853-1400
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>1170 PEACHTREE STREET, NE
<STREET2>SUITE 2400
<CITY>ATLANTA
<STATE>GA
<ZIP>30309-7676
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>L&C SPINCO INC
<DATE-CHANGED>20010629
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>BROWNING PETER C
<CIK>0001176402
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-16583
<FILM-NUMBER>08992590
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>C/O ENPRO INDUSTRIES INC
<STREET2>5605 CARNEGIE BLVD
<CITY>CHARLOTTE
<STATE>NC
<ZIP>28209-4674
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-08-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001144215</issuerCik>
        <issuerName>ACUITY BRANDS INC</issuerName>
        <issuerTradingSymbol>AYI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001176402</rptOwnerCik>
            <rptOwnerName>BROWNING PETER C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ACUITY BRANDS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1170 PEACHTREE STREET, NESUITE 2400</rptOwnerStreet2>
            <rptOwnerCity>ATLANTA</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30309</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>391</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>41.54</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>391</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13868</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Stock Units are accrued under the Issuer's Nonemployee Directors' Deferred Compensation Plan (formerly known as the Nonemployee Directors' Stock Unit Plan) and are payable in shares upon retirement in either lump sum or five annual installments.  Accruals include required and elective deferral of director fees.   During the Reporting Period, fees paid to the Reporting Person resulted in an increase in the number of units held.</footnote>
        <footnote id="F2">1-for-1</footnote>
        <footnote id="F3">Stock Units issued pursuant to the Plan are payable in common shares upon retirement in either a lump sum or five annual installments.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Peter C. Browning</signatureName>
        <signatureDate>2008-08-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
