EXHIBIT 5




                                 August 9, 2002



ProLogis
14100 East 35th Place
Aurora, Colorado 80011

                  Re:      Registration Statement on Form S-8
                           ProLogis 1997 Long-Term Incentive Plan

Ladies and Gentlemen:

                  We have acted as counsel to ProLogis, a Maryland real estate
investment trust (the "Trust"), in connection with the proceedings (the "Trust
Proceedings") taken and to be taken relating to the registration by the Trust of
an aggregate of 8,000,000 of its common shares, par value $.01 per share (the
"Common Shares"), with the Securities and Exchange Commission (the "SEC") in
connection with an amendment to the ProLogis 1997 Long-Term Incentive Plan (the
"Plan"). We have also participated in the preparation and filing with the SEC
under the Securities Act of 1933, as amended, of a registration statement on
Form S-8 (the "Registration Statement") relating to the Common Shares.

                  As counsel to the Trust, we have examined originals or copies
certified to our satisfaction of the Trust's Amended and Restated Declaration of
Trust and Amended and Restated Bylaws, resolutions of the Board of Trustees and
such other Trust records, instruments, certificates and documents and such
questions of law as we considered necessary or appropriate to enable us to
express this opinion. As to certain facts material to our opinion, we have
relied, to the extent we deem such reliance proper, upon certificates of public
officials and officers of the Trust. In rendering this opinion, we have assumed
the genuineness of all signatures, the authenticity of all documents submitted
to us as originals and the conformity to authentic original documents of
photostatic copies.

                  Based upon and subject to the foregoing and to the
assumptions, limitations and conditions set forth herein, we are of the opinion
that, upon completion of the Trust Proceedings, the Common Shares, when issued
and delivered in accordance with the Trust Proceedings and the Plan, will have
been legally issued, fully paid and nonassessable.

                  We hereby consent to the filing of this opinion as an exhibit
to the Registration Statement.

                                                    Very truly yours,




                                                    /s/ MAYER, BROWN, ROWE & MAW