Restricted Share Unit Plan

Exhibit 10.21 COGNOS INCORPORATED
2002-2005 RESTRICTED SHARE UNIT PLAN
(Adopted by the Cognos Board of Directors on September 25, 2002)

1. PURPOSE

The purpose of this 2002-2005 Restricted Share Unit Plan (the " Plan") of Cognos Incorporated (the " Corporation") and any present or future wholly owned subsidiary of the Corporation wherever located (each a " Subsidiary") is to provide grants (each an " Award") of Restricted Share Units (as defined below) to officers, directors and employees of the Corporation and its Subsidiaries. Any person to whom an Award has been granted under this plan is called a " Participant". A " Restricted Share Unit" means a right to receive, on the basis set out in the Plan, one (1) common share in the capital stock of the Corporation (a " Common Share").

For greater certainty, the Plan together with any trust established pursuant hereto shall be constituted as an "employee benefit plan" for the purposes of the Income Tax Act (Canada) (the "Tax Act"). No provision of the Plan shall be applied, interpreted or administered in a manner contrary to the requirements of the Tax Act for qualification of the Plan as such. For greater certainty, the grant of an Award represents a contingent entitlement of the Participant to whom it has been granted and the exchange of a Restricted Share Unit which is the subject of an Award for a Common Share shall be the payment of such share out of or under an employee benefit plan.

2. ADMINISTRATION OF THE PLAN

A. The Plan shall be administered by the Human Resources & Compensation Committee (the " Committee") of the Board of Directors of the Corporation (the " Board").

B. Subject to the terms of the Plan, the Committee shall have the authority to (a) determine the Participants of the Corporation and any Subsidiary (from among the class of individuals eligible under paragraph 1) to whom Awards may be granted; (b) determine the time or times at which Awards may be granted; (c) determine the limitations, restrictions, and conditions of any grant of Awards; (d) determine the time or times when each Restricted Share Unit which is the subject of an Award shall become exchangeable or exercisable for a Common Share and the duration of the exchange or exercise period; (e) interpret the Plan and prescribe and rescind rules and regulations relating to it; and (f) select on or more trustees (each a " Trustee" and collectively the " Trustees") and establish one or more agreements between the Corporation and each Trustee (each a " Trust Agreement") to provide for the purchase of Common Shares on the open market for exchange or exercise under the Plan and the administration of the policies and procedures governing such purchases. The interpretation and construction by the Committee of any provisions of the Plan or of any Awards granted under it is final unless otherwise determined by the Board. The Committee may from time to time adopt such rules and regulations for carrying out the Plan as it may consider appropriate. No member of the Board or the Committee shall be liable for any action or determination made in good faith with respect to the Plan or any Award granted under it.

C. The date of grant of an Award under the Plan will be the date specified by the Committee at the time it grants the Award. If no date is specified, the date will be the date of the grant.

D. Awards may be granted to members of the Board, including members of the Committee. All grants of Awards to members of the Board shall be made in accordance with the provisions of this Plan applicable to other eligible persons. Members of the Board who either (a) are eligible to receive grants of Awards pursuant to the Plan or (b) have been granted Awards may vote on any matters affecting the administration of the Plan or the grant of any Awards pursuant to the Plan, except that no such member shall act upon the granting to himself of Awards, but any such member may be counted in determining the existence of a quorum at any meeting of the Board during which such action is taken with respect to the granting of Awards to such member.

3. AWARDS

Subject to the requirements in this Plan, the Committee shall determine the number of Restricted Share Units which are granted pursuant to an Award and the terms and conditions of each Award. After the expiration and/or satisfaction of the applicable restrictions and conditions set forth in an Award Agreement (as defined below), a

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Participant may elect to exchange each Restricted Share Unit for one (1) Common Share. The delivery to the Participant of such Common Share shall be subject to (i) such trading restrictions as may be imposed by the Corporation from time to time and (ii) the delivery of such evidence as the Corporation's registrar and transfer agent may reasonably require confirming the eligibility of such Participant to own Common Shares under the ownership constraints applicable to shareholders of the Corporation.

4. STOCK

A. All stock delivered to the Participants under the Plan shall be authorized, issued and outstanding Common Shares, wh ...