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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001123292-09-000486.txt : 20090512
<SEC-HEADER>0001123292-09-000486.hdr.sgml : 20090512
<ACCEPTANCE-DATETIME>20090512204226
ACCESSION NUMBER:		0001123292-09-000486
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090509
FILED AS OF DATE:		20090512
DATE AS OF CHANGE:		20090512

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HACKETT GROUP, INC.
		CENTRAL INDEX KEY:			0001057379
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MANAGEMENT CONSULTING SERVICES [8742]
		IRS NUMBER:				650750100
		STATE OF INCORPORATION:			FL
		FISCAL YEAR END:			1228

	BUSINESS ADDRESS:	
		STREET 1:		1001 BRICKELL BAY DRIVE
		STREET 2:		SUITE 3000
		CITY:			MIAMI
		STATE:			FL
		ZIP:			33131
		BUSINESS PHONE:		3053758005

	MAIL ADDRESS:	
		STREET 1:		1001 BRICKELL BAY DRIVE
		STREET 2:		SUITE 3000
		CITY:			MIAMI
		STATE:			FL
		ZIP:			33131

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ANSWERTHINK INC
		DATE OF NAME CHANGE:	20000628

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ANSWERTHINK CONSULTING GROUP INC
		DATE OF NAME CHANGE:	19980608

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HARRIS JOHN R
		CENTRAL INDEX KEY:			0001079144

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-48123
		FILM NUMBER:		09820290

	MAIL ADDRESS:	
		STREET 1:		2201 CEDEAR SPRINGS RD
		STREET 2:		SUITE 701
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75201
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-05-09</periodOfReport>

    <issuer>
        <issuerCik>0001057379</issuerCik>
        <issuerName>HACKETT GROUP, INC.</issuerName>
        <issuerTradingSymbol>HCKT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001079144</rptOwnerCik>
            <rptOwnerName>HARRIS JOHN R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE HACKETT GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1001 BRICKELL BAY DRIVE, SUITE 3000</rptOwnerStreet2>
            <rptOwnerCity>MIAMI</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-05-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>833</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7742</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-05-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>833</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>833</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>833</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Upon vesting of the restricted stock units, the reporting person will receive shares of common stock on a one-for-one basis.</footnote>
        <footnote id="F2">The restricted stock units vested with respect to 1/3 of the units on May 9, 2008 and May 9, 2009, and will vest with respect to the remaining 1/3 of the units on May 9, 2010.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Frank A. Zommerfeld, Attorney-in-Fact</signatureName>
        <signatureDate>2009-05-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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