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                                                                    Exhibit 31.1

                   CAREY INSTITUTIONAL PROPERTIES 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 Carey Institutional
Properties 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          3/19/04                    Date          3/19/04

     /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)