UNITED
STATES


SECURITIES
AND EXCHANGE COMMISSION


Washington,
DC 20549








FORM
10-K





(Mark
One)




[X]
            ANNUAL
      REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF
      1934




For
      the fiscal year ended December
      31,
      2007




OR




[  ]
            TRANSITION
      REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF
      1934




For
      the transition period from 
      to




Commission
file number 333-130333-19







CMALT
      (CitiMortgage Alternative Loan Trust), Series 2007-A3(Exact
      name of issuing entity as specified in its
  charter)







Citicorp
      Mortgage Securities, Inc.(Exact
      name of depositor as specified in its
charter)







CitiMortgage,
      Inc.(Exact
      name of sponsor as specified in its
charter)







New
      York
            
            32-0199552,
      32-0199551 and 32-0199550(State
      or Other Jurisdiction of Incorporation or Organization of Issuing
      Entity)
            
            (I.R.S.
      Employer Identification Number of Issuing Entity)1000
      Technology Drive, O’Fallon, Missouri
            
            63368-2240(Address
      of Principal Executive
              Offices
      of Issuing Entity)
            
            (Zip
      Code)





Registrant’s
      telephone number, including area code (636)
      261-1313





Securities
Registered pursuant to Section 12(b) of the Exchange
Act:       NONE





Securities
Registered pursuant to Section 12(g) of the
Act:       NONE





Indicate
by check mark if the registrant is a well-known seasoned issuer, as defined in
Rule 405 of the Securities Act. [  ] Yes   [X]
No





Indicate
by check mark if the registrant is not required to file reports pursuant to
Section 13 or Section 15(d) of the Act. [  ]
Yes   [X] No





1








Indicate
by check mark whether the registrant: (1) has filed all reports required to be
filed by Section 13 or 15(d) of the Exchange Act during the preceding 12 months
(or such shorter period that the registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90
days.        [X]
Yes  [  ] No





Indicate
by check mark if disclosure of delinquent filers pursuant to Item 405 of
Regulation S-K is not contained herein, and will not be contained, to the best
of registrant’s knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.      [  ]  [Item
405 of Regulation S-K is not applicable.]





Indicate
by check mark whether the registrant is a large accelerated filer, an
accelerated filer, or a non-accelerated filer.  See definition of
“accelerated filer and large accelerated filer in Rule 12b-2 of the Exchange
Act.  (Check one):





Large
      Accelerated Filer  [   ]
            Accelerated
      Filer [   ]
            Non-Accelerated
      Filer [X]





Indicate
by check mark whether the registrant is a shell company (as defined in Rule
12b-2 of the Exchange Act).   [   ]
Yes   [X] No





State the
aggregate market value of the voting and non-voting common equity held by
non-affiliates computed by reference to the price at which the common equity was
last sold, or the average bid and asked price of such common equity, as of the
last business day of the registrant’s most recently completed second fiscal
quarter.  [Not applicable.]








PART
I




The
following items have been omitted pursuant to General Instruction J. to Form
10-K:





Item
1.          Business


Item
1A.       Risk Factors


Item
2.          Properties


Item
3.          Legal
Proceedings


Item
4.          Submission of
Matters to a Vote of Security Holders








Item
1B.       Unresolved Staff
Comments





None.







The
following substitute information is provided in accordance with General
Instruction J. to Form 10-K:




Item 1112(b) of Regulation AB
(Significant obligors of pool
assets)




No single
obligor represents more than 10% of the pool assets held by the issuing
entity.




Item 1114(b)(2) of Regulation
AB (Credit enhancement
and other support, except for certain derivative instruments) (Information
regarding significant enhancement providers)




No entity
or group of affiliated entities provides any external credit enhancement for the
certificates issued by the issuing entity.




Item 1115(b) of Regulation AB
(Certain derivative
instruments)




No entity
or group of affiliated entities provides derivative instruments having a
significance percentage of 10% or more.








2








Item
1117 of Regulation AB (Legal Proceedings)





There are
no legal proceedings that would be material to investors against the sponsor,
the depositor, the issuing entity, Citibank, N.A. (the paying agent,
authenticating agent and certificate registrar for the issuing entity), or to
CitiMortgage, Inc.’s knowledge, the trustee, nor does CitiMortgage, Inc. know of
any such proceeding contemplated by any governmental authorities.








PART
II








The
following items have been omitted pursuant to General Instruction J. of Form
10-K:





Item
5.        Market for Registrant’s Common
Equity, Related Stockholder Matters and Issuer Purchases of
EquitySecurities


Item
6.        Selected Financial
Data


Item
7.        Management’s Discussion and
Analysis of Financial Condition and Results of Operations


Item
7A.     Quantitative and Qualitative Disclosures About
Market Risk


Item
8.        Financial Statements and
Supplementary Data


Item
9.        Changes in Disagreements With
Accountants on Accounting and Financial Disclosure


Item
9A.     Controls and Procedures








Item
9B.    Other Information





None.









PART
III







The
following items have been omitted pursuant to General Instruction J. of Form
10-K:




Item
10.       Directors, Executive Officers and
Corporate Governance


Item
11.       Executive Compensation


Item
12.       Security Ownership of Certain
Beneficial Owners and Management and Related Stockholder Matters


Item
13.       Certain Relationships and Related
Transactions, and Director Independence


Item
14.       Principal Accounting Fees and
Services





The
following substitute information is provided in accordance with General
Instruction J. to Form 10-K:




Item 1119 of Regulation AB
(Affiliations and certain
relationships and related transactions)





The
information regarding this item has been filed in a 424(b)(5) filing dated March
28, 2007.


Item 1122 of Regulation AB
(Compliance with applicable
servicing criteria)




The
reports required by Item 1122(a) and (b) of, or relating to, all parties
determined by the registrant to be participating in the servicing function with
respect to the issuing entity are attached to this Form 10-K as Exhibits 33.1.1,
33.1.2, 33.1.3, 34.1.1, 34.1.2 and 34.1.3.




The
Agency and Trust division of Citibank, N.A. disclosed the following material
noncompliance with criteria applicable to them during the year ended December
31, 2007: 1122(d)(2)(i) – With respect to certain transactions for which the
transaction documents require that funds be deposited into the custodial bank
accounts on the day funds are received by the Agency and Trust division of
Citibank, N.A., funds were not deposited to the custodial bank accounts in
accordance with the terms of the transaction documents.  In a sample
of selected payments on pool assets received by The Agency and Trust division of
Citibank, N.A., this finding was identified once.  In that instance,
the funds received were deposited into the specified custodial account on the
day after the day they were received.  As the one-day delay only
impacted investment income to which the Agency and Trust division of Citibank,
N.A. was entitled as compensation for its services as securities administrator,
management believes that the delay did not affect the amount of any payments to
any security holder or to any transaction party other than the Agency and Trust
division of Citibank, N.A. 1122(d)(3)(ii) – With respect to certain remittances
during the reporting period, amounts due to investors were allocated and
remitted in accordance with distribution priority and other terms set forth in
the transaction agreements, but were not paid timely to investors.




Item
1123 of Regulation AB (Servicer compliance statement)





The
statement required by Item 1123 is attached to this Form 10-K as Exhibit
35.1.










3








PART
IV







Item
      15.
            Exhibits,
      Financial Statement Schedules(a)(1)
            Not
      applicable.(a)(2)
            Not
      applicable.(a)(3)
            ExhibitsExhibit
      Number
            Description4.1
            Pooling
      and Servicing Agreement, dated as of March 1, 2007, incorporated by
      reference from Exhibit 4.1 of the Issuing Entity’s Current Report on Form
      8-K filed with the Commission on April 6, 2007.10.1
            Form
      of Mortgage Loan Purchase Agreement, dated March 1, 2007, incorporated by
      reference from Exhibit 10.1 of the Issuing Entity’s Current Report on Form
      8-K filed with the Commission on April 6, 2007.31.1
            Certification
      pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 and relevant
      rules and regulations of the Commission, dated March 28,
2008.33.1.1
            Management
      Assessment of Compliance with Applicable Servicing Criteria, dated
      February 22, 2008, of CitiMortgage, Inc.33.1.2
            Management
      Assertion of Compliance, dated February 29, 2008, of the Agency and Trust
      division of Citibank, N.A.33.1.3
            Management
      Assessment of Compliance with Applicable Servicing Criteria, dated
      February 22, 2008, of Citibank, N.A.34.1.1
            Report
      of Independent Registered Public Accounting Firm, dated February 22, 2008,
      of KPMG LLP, relating to Exhibit 33.1.1.34.1.2
            Report
      of Independent Registered Public Accounting Firm, dated February 29, 2008,
      of KPMG LLP, relating to Exhibit 33.1.2.34.1.3
            Report
      of Independent Registered Public Accounting Firm, dated February 22, 2008,
      of KPMG LLP, relating to Exhibit 33.1.3.35.1
            Servicer
      Compliance Statement of CitiMortgage, Inc., dated February 22,
      2008.







4







SIGNATURES









Pursuant to the requirements of Section
13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly
caused this report to be signed on its behalf by the undersigned, thereunto duly
authorized.




CMALT
(CitiMortgage Alternative Loan Trust), Series 2007-A3




By: CitiMortgage, Inc., as
Servicer




By: /s/
Herb
Gover


Herb
Gover


Executive
Vice President, North American Consumer Asset Operations


March 28,
2008





























































































5







INDEX
TO EXHIBITS










Exhibit
      Number
            Description4.1
            Pooling
      and Servicing Agreement, dated as of March 1, 2007, incorporated by
      reference from Exhibit 4.1 of the Issuing Entity’s Current Report on Form
      8-K filed with the Commission on April 6, 2007.10.1
            Form
      of Mortgage Loan Purchase Agreement, dated March 1, 2007, incorporated by
      reference from Exhibit 10.1 of the Issuing Entity’s Current Report on Form
      8-K filed with the Commission on April 6, 2007.31.1
            Certification
      pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 and relevant
      rules and regulations of the Commission, dated March 28,
2008.33.1.1
            Management
      Assessment of Compliance with Applicable Servicing Criteria, dated
      February 22, 2008, of CitiMortgage, Inc.33.1.2
            Management
      Assertion of Compliance, dated February 29, 2008, of the Agency and Trust
      division of Citibank, N.A.33.1.3
            Management
      Assessment of Compliance with Applicable Servicing Criteria, dated
      February 22, 2008, of Citibank, N.A.34.1.1
            Report
      of Independent Registered Public Accounting Firm, dated February 22, 2008,
      of KPMG LLP, relating to Exhibit 33.1.1.34.1.2
            Report
      of Independent Registered Public Accounting Firm, dated February 29, 2008,
      of KPMG LLP, relating to Exhibit 33.1.2.34.1.3
            Report
      of Independent Registered Public Accounting Firm, dated February 22, 2008,
      of KPMG LLP, relating to Exhibit 33.1.3.35.1
            Servicer
      Compliance Statement of CitiMortgage, Inc., dated February 22,
      2008.









































6