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                            OFFICERS' CERTIFICATIONS

                                                                    EXHIBIT 99.1



                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                                 /s/ Richard S. Ziman
                                                  ------------------------------
                                                  Richard S. Ziman
                                                  Chairman of the Board and
                                                  Chief Executive Officer
                                                  Arden Realty, Inc.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.

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                    CERTIFICATION OF CHIEF FINANCIAL OFFICER

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                                 /s/ Richard S. Davis
                                                  ------------------------------
                                                  Richard S. Davis
                                                  Senior Vice President and
                                                  Chief Financial Officer
                                                  Arden Realty, Inc.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.

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                           CERTIFICATION OF PRESIDENT

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                             /s/ Victor J. Coleman
                                              ----------------------------------
                                              Victor J. Coleman
                                              President, Chief Operating Officer
                                              and Director
                                              Arden Realty, Inc.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.

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                    CERTIFICATION OF EXECUTIVE VICE PRESIDENT

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                          /s/ Andrew J. Sobel
                                           -------------------------------------
                                           Andrew J. Sobel
                                           Executive Vice President -- Strategic
                                           Planning and Operations
                                           Arden Realty, Inc.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.

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                     CERTIFICATION OF SENIOR VICE PRESIDENT

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                              /s/ Robert C. Peddicord
                                               ---------------------------------
                                               Robert C. Peddicord
                                               Senior Vice President -- Leasing
                                               and Operations
                                               Arden Realty, Inc.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.

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                        CERTIFICATION OF GENERAL COUNSEL

Pursuant to 18 U.S.C. Section 1350, as created by Section 906 of the
Sarbanes-Oxley Act of 2002, the undersigned officer of Arden Realty, Inc. (the
"Company"), hereby certifies, to such officer's knowledge, that:

               (i) the accompanying quarterly report on Form 10-Q of the Company
for the period ended March 31, 2003 (the "Report") fully complies with the
requirements of Section 13(a) or Section 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended; and

               (ii) the information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

Date: May 12, 2003                                 /s/ David A. Swartz
                                                  ------------------------------
                                                  David A. Swartz
                                                  General Counsel and Secretary
                                                  Arden Realty, Inc.


A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.

The foregoing certification is being furnished solely to accompany the Report
pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be
incorporated by reference into any filing of the Company, whether made before or
after the date hereof, regardless of any general incorporation language in such
filing.