October 4, 2007

MDA Awarded Contract To Build Canadian Information Solution For Surveillance Of Space Objects

Richmond, B.C. - MacDonald, Dettwiler and Associates Ltd. (TSX: MDA), a provider of essential information solutions, announced today that the company has won an approximately $65 Million contract from Canada's Department of National Defence (DND) to deliver an information solution called SAPPHIRE for the surveillance of space objects. SAPPHIRE is DND's first dedicated space mission and will support Canada's NORAD commitments with the delivery of critical information.

SAPPHIRE will feature a space-based data collection platform for continuous surveillance of manmade and natural objects in medium to high Earth orbits (6,000 to 40,000 km). The data collected will be processed by a ground-based system and the results will be used to update the U.S. Satellite Catalogue that is used by both NORAD and Canada to provide space situational awareness.

MDA will lead a team comprised of COMDEV of Cambridge, Ontario, and SSTL of Surrey, England. The four-year contract has the potential for a future extension for mission support, operations, and maintenance. It follows a design phase previously awarded to MDA.

About MDA

MDA provides advanced information solutions that capture and process vast amounts of data, produce essential information, and improve the decision making and operational performance of business and government organizations worldwide.

Focused on markets and customers with strong repeat business potential, MDA delivers a broad spectrum of earth and space based information solutions, ranging from complex operational systems, to tailored information services, to electronic information products.

MDA employs more than 3,000 people in locations across the United States, the United Kingdom, and Canada. The Company's common shares trade on the Toronto Stock Exchange under the symbol. TSX:MDA.

Related Websites:
www.mdacorporation.com

For more information, please contact:

Wendy Keyzer
External Relations
MDA
Telephone: 604-231-2743
E-mail: wendy@mdacorporation.com

Forward-Looking Statement
This release contains forward-looking statements and information, which reflect the current view of MacDonald, Dettwiler and Associates Ltd. with respect to future events and financial performance. Any such forward-looking statements are subject to risks and uncertainties and MDA's actual results of operations could differ materially from historical results or current expectations. Additional information on these and other potential factors that could affect MDA's financial results are detailed in documents filed from time to time with the applicable Canadian securities regulatory authorities.

The Toronto Stock Exchange has neither approved nor disapproved the form or content of this release.

For more information, please contact:

Wendy Keyzer
MDA External Relations
Telephone: 604-231-2743
E-mail: wendy@mdacorporation.com