[LETTERHEAD OF HALE AND DORR LLP]

                                                            Exhibit 5.1


                                    July 31, 2001


MicroStrategy Incorporated
1861 International Drive
McLean, Virginia 22102

     Registration Statement on Form S-3
     ----------------------------------

Ladies and Gentlemen:


     This opinion is furnished to you in connection with a Registration
Statement on Form S-3 (the "Registration Statement") to be filed with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended (the "Securities Act"), for the registration of an aggregate
of 1,900,000 shares of the class A common stock, $.001 par value per share (the
"Shares"), of MicroStrategy Incorporated, a Delaware corporation (the
"Company"). The Shares will be issued upon exercise of certain warrants (the
"Warrants") to be issued by the Company pursuant to a settlement agreement among
the Company, certain of its officers and directors and plaintiffs' counsel,
approved by the United States District Court for the Eastern District of
Virginia on April 2, 2001, relating to a consolidated class action lawsuit filed
against the Company, certain of its officers and directors and its independent
accountants.


     We have acted as counsel for the Company in connection with the
registration of the Shares.  We have examined signed copies of the Registration
Statement to be filed with the Commission.  We have also examined and relied
upon the minutes of meetings of the stockholders and the Board of Directors of
the Company as provided to us by the Company, stock record books of the Company
as provided to us by the Company, the Certificate of Incorporation and By-Laws
of the Company, each as restated and/or amended to date, and such other
documents as we have deemed necessary for purposes of rendering the opinions
hereinafter set forth.

     In our examination of the foregoing documents, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all documents submitted to
us as copies, the authenticity of the originals of such latter documents and the
legal competence of all signatories to such documents.

     We assume that the appropriate action will be taken, prior to the offer and
sale of the Shares, to register and qualify the Shares for sale under all
applicable state securities or "blue sky" laws.



July 31, 2001

Page 2


     We express no opinion herein as to the laws of any state or jurisdiction
other than the state laws of the Commonwealth of Massachusetts, the Delaware
General Corporation Law statute and the federal laws of the United States of
America.

     Based upon and subject to the foregoing, we are of the opinion that the
Shares have been duly authorized and, when issued in accordance with the terms
of the Company's Certificate of Incorporation and the Warrants, will be validly
issued, fully paid and nonassessable.

     It is understood that this opinion is to be used only in connection with
the offer and sale of the Shares while the Registration Statement is in effect.

     Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters.

     We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our
name therein and in the related prospectus under the caption "Legal Matters."
In giving such consent, we do not hereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act or the
rules and regulations of the Commission.

                                            Very truly yours,

                                            /s/ Hale and Dorr LLP


                                            HALE AND DORR LLP