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                                                                    Exhibit 31.1

                  CORPORATE PROPERTY ASSOCIATES 12 INCORPORATED

                  CERTIFICATIONS OF CO-CHIEF EXECUTIVE OFFICERS
                           PURSUANT TO RULE 15d-14(a)

We, William Polk Carey and Gordon F. DuGan, certify that:

1. We have reviewed this Annual Report on Form 10-K of Corporate Property
Associates 12 Incorporated (the "Registrant");

2. Based on our knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this annual
report;

3. Based on our knowledge, the financial statements, and other financial
information included in this annual report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
Registrant as of, and for, the periods presented in this annual report;

4. The Registrant's other certifying officer and we are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial
reporting (as defined in Exchange Act Rules 13a-15(f) and 15(d)-15(f)) for the
Registrant and we have:

      a)    designed such disclosure controls and procedures, or caused such
            disclosure controls and procedures to be designed under our
            supervision, to ensure that material information relating to the
            Registrant, including its consolidated subsidiaries, is made known
            to us by others within those entities, particularly during the
            period in which this annual report is being prepared;

      b)    designed such internal control over financial reporting, or caused
            such internal control over financial reporting to be designed under
            our supervision, to provide reasonable assurance regarding the
            reliability of financial reporting and the preparation of financial
            statements for external purposes in accordance with generally
            accepted accounting principles;

      c)    evaluated the effectiveness of the Registrant's disclosure controls
            and procedures and presented in this annual report our conclusions
            about the effectiveness of the disclosure controls and procedures,
            as of the end of the period covered by this annual report based on
            such evaluation; and

      d)    disclosed in this annual report any change in the Registrant's
            internal control over financial reporting that occurred during the
            Registrant's fourth fiscal quarter that has materially affected, or
            is reasonably likely to materially affect, the Registrant's internal
            control over financial reporting; and

5. The Registrant's other certifying officer and we have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
Registrant's auditors and the audit committee of the Registrant's board of
directors (or persons performing the equivalent functions):

      a)    all significant deficiencies and material weaknesses in the design
            or operation of internal controls over financial reporting which are
            reasonably likely to adversely affect the Registrant's ability to
            record, process, summarize and report financial information; and

      b)    any fraud, whether or not material, that involves management or
            other employees who have a significant role in the Registrant's
            internal controls over financial reporting.

Date              3/10/04                  Date              3/10/04
         ---------------------------                --------------------------


         /s/ William Polk Carey                     /s/ Gordon F. DuGan
         ---------------------------                --------------------------

         William Polk Carey                         Gordon F. DuGan
         Chairman                                   Vice Chairman
         (Co-Chief Executive Officer)               (Co-Chief Executive Officer)


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