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                                                          Exhibit 5.1


                                                          Matter Number: 1009215


                      [OSLER, HOSKIN & HARCOURT LETTERHEAD]

June 1, 2000


Delano Technology Corporation
302 Town Centre Blvd.
Markham, Ontario
L3R 0E8
Canada

Dear Sirs:

Re:      Delano Technology Corporation Employee Stock Purchase Plan
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We are Canadian counsel to Delano Technology Corporation (the "Corporation"). We
are providing this opinion in connection with the filing by the Corporation with
the United States Securities and Exchange Commission of the Registration
Statement on Form S-8 (the "Registration Statement") registering 1,000,000
Common Shares of the Corporation (the "Plan Shares") for issuance under the
Corporation's Employee Stock Purchase Plan (the "Plan").

In connection with the opinions expressed herein we have considered such
questions of law and examined such corporate records, certificates and other
documents and conducted such other examinations as we have considered necessary
for the purposes of the opinions hereinafter expressed. In all such examinations
we have assumed the legal capacity of all individuals, the genuineness of all
signatures, the authenticity of all documents submitted to us as originals and
the conformity to authentic original documents of all documents submitted to us
as certified, conformed, photostatic or facsimile copies.

We have also relied, as to certain factual matters, upon a certificate of David
Lewis, the General Counsel and Secretary of the Company, dated of even date
herewith.

We are solicitors qualified to practice law in the Province of Ontario and we
express no opinion as to any laws or matters governed by any laws other than the
laws of the Province of Ontario and the federal laws of Canada applicable
therein. We have not made any independent examination of the laws of any
jurisdiction other than the laws of the Province of Ontario and the laws of
Canada in force in the Province of Ontario.


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Based and relying upon and subject to the foregoing, we are of the opinion that:

1.       All necessary corporate action has been taken by the Corporation to
         adopt the Plan.

2.       When (i) options to purchase the Plan Shares are granted in accordance
         with the terms of the Plan; (ii) such options are duly exercised in
         accordance with the terms of the Plan; (iii) the Plan Shares are issued
         in accordance with the terms of the various agreements and instruments
         relating thereto; (iv) the prescribed exercise price is paid to the
         Corporation in accordance with the terms of the Plan; and (v) all other
         conditions contained therein have been satisfied or waived, the Plan
         Shares will be validly issued and outstanding as fully paid and
         non-assessable shares.

We acknowledge that we are referred to in Item 8 of the Registration Statement
and we hereby consent to the use of this opinion and consent for filing with the
Registration Statement as Exhibits 5.1 and 23.1 thereto.

This opinion is rendered solely for the benefit of Delano Technology Corporation
and may not be used or relied upon for any other purpose or used or relied upon
by any other person without our prior written consent.

Yours very truly,

OSLER, HOSKIN & HARCOURT LLP


/s/ Osler, HOSKIN & HARCOURT LLP



EAS/DAB