Exhibit 5.1
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                                    December 5, 2001

SeaChange International, Inc.
124 Acton Street
Maynard, MA 01754

     Re:  Registration Statement on Form S-3
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Ladies and Gentlemen:

     We are counsel to SeaChange International, Inc., a Delaware corporation
(the "Company"), and have represented the Company in connection with the
preparation and filing of the Company's Registration Statement on Form S-3 (the
"Registration Statement"), relating to the public offering of an aggregate of up
to 3,450,000 shares of the Company's common stock, $.01 par value per share (the
"Common Stock"), of which (a) 2,790,000 shares will be issued and sold to the
underwriters by the Company; (b) 210,000 shares will be sold to the underwriters
by certain stockholders of the Company (the "Selling Stockholders"); and (c)
450,000 shares may be purchased by the underwriters from the Company to cover
over-allotments, if any (collectively, the "Shares").

     We have reviewed the corporate proceedings taken by the Board of Directors
of the Company with respect to the authorization and issuance of the Shares.  We
have also examined and relied upon originals or copies, certified or otherwise
authenticated to our satisfaction, of all corporate records, documents,
agreements or other instruments of the Company and have made all investigations
of law and have discussed with the Company's officers all questions of fact that
we have deemed necessary or appropriate.

     Based upon and subject to the foregoing, we are of the opinion that (i) the
Shares to be issued and sold by the Company have been duly and validly
authorized and, when sold in the manner contemplated by the underwriting
agreement (the "Underwriting Agreement") substantially in the form to be filed
as Exhibit 1.1 to the Registration Statement and upon receipt by the Company of
payment therefor as provided in the Underwriting Agreement, will be validly
issued, fully paid and non-assessable; and (ii) the Shares to be sold by the
Selling Stockholders are duly and validly authorized, validly issued, fully paid
and non-assessable.

     We hereby consent to the filing of this opinion as Exhibit 5.1 to the
Registration Statement and to the reference to our firm in the Prospectus
contained in the Registration Statement under the caption "Legal Matters."

                                    Very truly yours,

/s/ Testa, Hurwitz & Thibeault, LLP

                                    TESTA, HURWITZ & THIBEAULT, LLP