Exhibit 5.1


Gentia Software Plc
Tuition House
St. George's Road
Wimbledon
London

SW19 4EU

14 March 2000

Dear Sirs

We have acted as English legal advisers to Gentia Software Plc (the "COMPANY"),
a public limited company incorporated in England and Wales, with respect to the
Company's Registration Statement on Form F-3 (the "REGISTRATION STATEMENT") to
be filed by the Company with the U.S. Securities and Exchange Commission on or
about 13 March 2000, in connection with the registration by the Company, under
the Securities Act 1933, as amended, of an aggregate of 2,648,647 American
Depositary Shares representing ordinary shares of par value (pound)0.15 per
share in the Company (the "SHARES").

We have examined, among other things, originals and/or copies of such documents,
certificates and records as we have deemed necessary and appropriate for the
purpose of preparing this opinion.

We have assumed without investigation the authenticity and completeness of all
documents submitted to us as originals or copies, the genuineness of all
signatories and the conformity to original documents of all copies.




We have assumed that at the date of allotment of any of the Shares the Company
is solvent and the Company has not by such date passed a voluntary winding-up
resolution, no petition has been presented or order made for the winding-up,
dissolution or administration of the Company and no receiver, administrative
receiver, administrator or similar officer has been appointed in relation to the
Company or any of its assets by the date of such allotment.

We have also made such examination of English law as we have felt necessary in
order to render this opinion. We have made no investigation, and express no
opinion, as to any law other than English law in force at and as interpreted at
the date of this opinion. We are not qualified to, and we do not, express an
opinion on the laws of any other jurisdiction.

Based on the foregoing and the following restrictions, we are of the opinion
that the board of directors of the Company has authority to allot the Shares
and, when allotted by the board of directors, the Shares will be legally issued,
fully paid, and not subject to any calls under the laws of England and Wales.

The following restrictions apply to the opinion given in the preceding
paragraph:

1.   We have assumed that the board of directors will allot the Shares in
     accordance with all necessary procedures contained in English law and the
     Company's Articles of Association.

2.   We have assumed that upon allotment the directors will duly enter the
     allotees' names in the register of members.

3.   The directors' authority to allot shares, given by ordinary resolution on 2
     February 2000 is for a period of 5 years from 2 February 2000.


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4.   The board of directors has expressed its intention to seek a renewal of
     this authority annually but, if the renewal is not obtained, it will lapse
     after 5 years from the above date or on the expiry date of the last
     subsequent renewal of authority.

5.   The Company has by special resolution disapplied statutory pre-emption
     rights on allotment of shares for the term of the above authority. The
     disapplication of pre-emption rights ceases to have effect if the authority
     to allot shares lapses. The period for which any renewal of this
     dissapplication can be made is limited to such period which, at the time of
     such renewal, is equal to the period of the directors' authority to allot
     shares.

6.   The Company presently has sufficient authorised unissued share capital to
     issue the Shares. If the Company issues ordinary shares so that the balance
     of ordinary shares of (pound)0.15 each contained in its authorised unissued
     share capital is less than the number of Shares, then the directors of the
     Company will not have the authority to allot the excess Shares.

7.   It is open to a Company to change its articles of association by special
     resolution and/or to change its authorised share capital by ordinary
     resolution. It is also open to a Company by ordinary resolution to revoke
     the directors' authority to allot shares and by special resolution to
     revoke the disapplication of statutory pre-emption rights. Such changes
     could mean that the directors of the Company will not have or will have
     limited authority to allot the Shares and could remove the statutory
     disapplication of pre-emption rights or create non statutory pre-emption
     rights.



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8.   We have assumed that the Company has not, without our knowledge, held any
     general meetings of its shareholders since 2 February 2000.

9.   We have relied upon a statement of fact from the Company that the board of
     directors has not, without our knowledge, allotted, or entered into any
     unconditional contract to allot, any shares under its authority since 27
     September 1999 which would result in the Company not having sufficient
     authorised unissued share capital to issue the Shares.

We give no opinion as the application of United States federal or state laws,
including the "Blue Sky" or securities laws of the various states.

We hereby consent to being named as counsel for the Company in the Registration
Statement and under the caption "Legal Matters" in the prospectus included in
the Registration Statement and to the filing of this opinion as an exhibit to
the Registration Statement.

This opinion is to be governed by and constructed in accordance with English
law.

Yours faithfully

FIELD FISHER WATERHOUSE



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