
                                  UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934


Date of report (Date of earliest event reported)             June 29, 2006
                                                  ------------------------------


                   Citigroup Commercial Mortgage Trust 2006-C4
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                       (Exact nameName of the Issuing Entity)
           
          Commission File Number of the Issuing Entity: 333-132746-01

                     Citigroup Global Markets Realty Corp.,
      PNC Bank, National Association and Barclays Capital Real Estate Inc.
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             (Exact nameName of the Sponsor as specified in its charter)

                  Citigroup Commercial Mortgage Securities Inc.
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           (Exact name of the Registrant as specified in its charter)
              Commission File Number of the Registrant: 333-132746


               Delaware                                             333-132746-01                        13-3439681
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     (State or Other Jurisdiction                (Commission                       (IRS Employer
           of Incorporation)                                 File Number)               Identification No.)

     388 Greenwich Street, New York, New York                                              10013
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     (Address of Principal Executive Offices)                                          (Zip Code)

Registrant's telephone number, including area code       (212) 816-6000
                                                   -----------------------------

                                       N/A
--------------------------------------------------------------------------------
          (Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ _]   Written communications pursuant to Rule 425 under the Securities Act (17
     CFR 230.425)

[ _]   Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
     240.14a-12)

[ _]   Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange
     Exchange Act (17 CFR 240.14d-2(b))

[ _]   Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
     Exchange Act (17 CFR 240.13e-4(c))





Section 1 - Registrant's Business and Operations

Item 1.01   Entry into a Material Definitive Agreement.

              On June 29, 2006, a pooling and servicing agreement dated as of June 1,
2006 (the "Pooling and Servicing Agreement"), was entered into by and among
Citigroup Commercial Mortgage Securities Inc. as depositor (the "Registrant"),
Midland Loan Services, Inc. as master servicer, J.E. Robert Company, Inc. as
special servicer and LaSalle Bank National Association as trustee. The Pooling
and Servicing Agreement was entered into for the purpose of issuing a single
series of certificates, entitled Citigroup Commercial Mortgage Trust 2006-C4
(the "Citigroup Commercial Mortgage Trust 2006-C4"), Commercial Mortgage
Pass-Through Certificates, Series 2006-C4 (the "Certificates"). The Pooling and
Servicing Agreement is attached as Exhibit 4.1 hereto. Certain classes
 of the 
Certificates, designated as Class A-1, Class A-2, Class A-SB, Class A-3,
Class Class
A-1A, Class A-M, Class A-J, Class B, Class C and Class D (collectively,
the the
"Publicly-Offered Certificates") were registered under the Registrant's
registration statement on Form S-3 (Registration No. 333-132746). The
Publicly-Offeredand Certificates were sold to 
Citigroup Global Markets Inc.
("Citigroup"), Barclays Capital Inc., PNC Capital Markets LLC, 
Banc of America
 Securities LLC and Deutsche Bank Securities Inc. (collectively, the
the "Underwriters"), pursuant to an underwriting agreement dated as of June 20, 2006
2006 (the "Underwriting Agreement"), between the Registrant and the 
Underwriters. The Underwriting Agreement is attached as Exhibit 1.1 hereto.
Certain of the mortgage loans backing the Publicly-Offered Certificates (the
"CGMRC Mortgage Loans") were acquired by the Registrant from Citigroup Global
Markets Realty Corp. ("CGMRC") as seller pursuant to a mortgage loan purchase
agreement dated as of June 20, 2006 (the "CGMRC Mortgage Loan Purchase
Agreement"), which is attached hereto as Exhibit 99.1. Certain other of the 
mortgage loans backing the Publicly-Offered
 Certificates (the "PNC Bank Mortgage 
Loans") were acquired by the Registrant
 from PNC Bank, National Association 
("PNC Bank") as seller pursuant to a
 mortgage loan purchase agreement dated as 
of June 20, 2006 (the "PNC Bank
 Mortgage Loan Purchase Agreement"), which is
attached hereto as Exhibit 99.2. The remaining mortgage loan backing the
Publicly-Offered Certificates (the "BCRE Mortgage Loan"; the CGMRC Mortgage
Loans, the PNC Bank Mortgage Loans and the BCRE Mortgage Loan, collectively, the
"Mortgage Loans") was acquired by the Registrant from Barclays Capital Real
Estate Inc. ("BCRE") as seller pursuant to a mortgage loan purchase agreement
dated as of June 20, 2006 (the "BCRE Mortgage Loan Purchase Agreement"; the
CGMRC Mortgage Loan Purchase Agreement, the PNC Bank Mortgage Loan Purchase
Agreement and the BCRE Mortgage Loan Purchase Agreement, collectively, the
"Mortgage Loan Purchase Agreements"), which is attached hereto as Exhibit 99.3.

              Each Mortgage Loan Purchase Agreement contains representations and
warranties made by the related seller (CGMRC, PNC Bank or BCRE, as the case may
be) to the Registrant with respect to the Mortgage Loans sold by such seller to
the Registrant.

         Certain

Section of9 the- termsFinancial andStatements conditions of the Pooling and ServicingExhibits
Agreement,
Item the9.01 UnderwritingFinancial AgreementStatements and the Mortgage Loan Purchase AgreementsExhibits.
have
     Listed beenbelow describedare inthe afinancial filing previously made on June 26statements, 2006pro onforma behalffinancial ofinformation
theand Registrantexhibits, whichif filingany, wasfiled madeas pursuanta topart Ruleof 424this report:

(ba)(5) ofFinancial the
Securitiesstatements Act of 1933,businesses asacquired:

     Not amended,applicable.

(b) underPro theforma Registrant'sfinancial Forminformation:

     Not S-3 registrationapplicable.
statement
(c) numberShell 333-132746-01,company fortransactions:

     Not theapplicable.

(d) CitigroupExhibits:

Exhibit Commercial Mortgage TrustNo.   Description
2006-C4, and the description of those agreements contained in that filing is----------   -----------
hereby incorporated herein by reference1.1           Underwriting A copy of the Agreement
4.1           Pooling and Servicing
Agreement, the Underwriting Agreement
5.1           Legality andOpinion
8.1           Tax theOpinion
99.1          CGMRC Mortgage Loan Purchase AgreementsAgreement
will99.2          PNC beBank filedMortgage subsequentlyLoan asPurchase exhibits to a separate Current Report on Form 8-KAgreement
filed99.3          BCRE by the Registrant for the Citigroup Commercial Mortgage TrustLoan 2006-C4.Purchase Agreement

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                                   SIGNATURES

              Pursuant to the requirements of the Securities Exchange Act of 1934,
the the
Registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.


Date:  June 30July 14, 2006


                                                                         CITIGROUP COMMERCIAL MORTGAGE 
                                        SECURITIES INC.


                                                                         By: /s/ Angela Vleck
                                                                                 ---------------------------------
                                        Name: Angela Vleck
                                        Title: Vice President


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                                  EXHIBIT INDEX

                   The following exhibits are filed herewith:

Exhibit No.
-----------
                                 Name:  Angela1.1           Underwriting VleckAgreement
                                 Title:4.1           Pooling Viceand PresidentServicing Agreement
5.1           Legality Opinion
8.1           Tax Opinion
                                       99.1          CGMRC Mortgage Loan Purchase Agreement
99.2          PNC Bank Mortgage Loan Purchase Agreement
99.3          BCRE Mortgage Loan Purchase Agreement


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Filing Compare · Citigroup Commercial Mortgage Trust 2006-C4
