EXHIBIT 5.1

July 17, 1998

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D. C. 20549-1004

Re:  Comverse Technology, Inc.

Gentlemen:

I have acted as legal counsel to Comverse Technology, Inc., a New York
corporation (the "Company"), in connection with the registration, pursuant to a
Registration Statement on Form S-8 (Registration No. 333-44429 ) under the
Securities Act of 1933, as amended, (the "Registration Statement") of an
aggregate of 9,500,343 shares of Common Stock of the Company, par value $0.10
per share ("Common Stock"), issuable upon the exercise of options ("Options")
which have been or may be granted under the 1989 Stock Option Plan, 1992
Directors' Stock Option Plan, 1994 Stock Incentive Plan, 1995 Director Stock
Option Plan, Amended and Restated 1996 Stock Incentive Plan and the Nonstatutory
Stock Option Agreement of Boston Technology, Inc.  and the 1987 Stock Option
Plan, 1994 Stock Option Plan, 1995 Stock Option Plan, 1996 Stock Option Plan,
1997 Stock Incentive Compensation Plan and 1997 Employee Stock Purchase Plan of
the Company (collectively, the "Plans"), including the registration for resale,
pursuant to a prospectus prepared in accordance with Part I of Form S-3, of an
aggregate of 212,000 shares of Common Stock, as set forth in Post-Effective
Amendment No. 1 to the Registration Statement.

I have examined originals, or copies certified to my satisfaction, of the
Certificate of Incorporation and By-Laws of the Company, the minutes and other
records of the proceedings of the Board of Directors and of the Stockholders of
the Company, the Plans and such other documents, corporate and public records,
agreements, and certificates of officers of the Company and of public and other
officials, and I have considered such questions of law, as I have deemed
necessary as a basis for the opinions hereinafter expressed.  In such
examination I have assumed the genuineness of all signatures and the
authenticity of all documents submitted to me as originals and the conformity to
original documents of all documents submitted to me as certified or photostatic
copies.

Based on and subject to the foregoing, I hereby advise you that, in my opinion,
the issuance of shares of Common Stock, upon exercise of the Options in
accordance with the provisions and subject to the conditions set forth in the
Plans and in the agreements executed thereunder governing the issuance and
exercise of the Options, has been duly authorized and, when the consideration
for such shares has been received by the Company and such shares have been
issued in accordance with and subject to such terms and conditions, such shares
of Common Stock will be legally issued, fully paid and nonassessable.

I hereby consent to the filing of this opinion with the Securities and Exchange
Commission in connection with the Registration Statement.

Very truly yours,


/S/ William F. Sorin