<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-11-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001373561</issuerCik>
        <issuerName>NewStar Financial, Inc.</issuerName>
        <issuerTradingSymbol>NEWS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001408853</rptOwnerCik>
            <rptOwnerName>Corsair Capital LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>717 FIFTH AVENUE, 24TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2007-11-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2319386</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8024358</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Consists of 2,209,238 shares held directly by Corsair III Financial Services Capital Partners, L.P. (&quot;Corsair III&quot;) and
 110,148 shares held directly by Corsair III Financial Services Offshore 892 Partners, L.P. (&quot;Corsair III Offshore&quot;).
 Corsair III Management, L.P. is the General Partner of Corsair III and Corsair III Offshore.  The Reporting Person is the
 General Partner of Corsair III Management, L.P.</footnote>
        <footnote id="F2">Consists of (a) the securities listed in Column 4 and (b) 5,704,972 shares held directly by J.P. Morgan Corsair II Capital
 Partners, L.P. (&quot;Corsair II&quot;), including 200,174 shares which may be acquired by Corsair II by exercise at any time at the
 option of Corsair II of one warrant.  The General Partner of Corsair II is Corsair II, L.P., the General Partner of Corsair
 II, L.P. is Corsair II, L.L.C., and the Managing Member of Corsair II, L.L.C. is Corsair PTJB, LLC.  The Reporting Person is
 the Manager of Corsair PTJB, LLC.</footnote>
        <footnote id="F3">The Reporting Person is filing solely in its capacity as General Partner of Corsair III Management, L.P. and as Manager of
 Corsair PTJB, LLC. By reason of the provisions of Rule 13d-3(a) of the Securities Exchange Act of 1934, the Reporting Person
 and Corsair III Management L.P. may be deemed to beneficially own the securities held by Corsair III and Corsair III
 Offshore, although each of the Reporting Person and Corsair III Management L.P., respectively, disclaims beneficial
 ownership of such securities except to the extent of their respective pecuniary interests therein. (Text continues in Note
 4).</footnote>
        <footnote id="F4">(Text continued from Note 3) By reason of the provisions of Rule 13d-3(a) of the Securities Exchange Act of 1934, the
 Reporting Person, Corsair II, L.P., Corsair II, L.L.C. and Corsair PTJB, LLC may be deemed to beneficially own the
 securities held by Corsair II, although each of the Reporting Person, Corsair II, L.P., Corsair II, L.L.C. and Corsair PTJB,
 LLC, respectively, disclaims beneficial ownership of such securities except to the extent of their respective pecuniary
 interests therein.  The Reporting Person holds the securities indirectly through Corsair II, Corsair III and Corsair III
 Offshore.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Amy M. Soeda, Chief Financial Officer of the Reporting Person</signatureName>
        <signatureDate>2007-12-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
