For immediate release: July 31, 2006

MDA to study an Italy-Canada Hyperspectral Mission

Richmond, B.C. - MacDonald, Dettwiler and Associates Ltd. (TSX: MDA), a provider of essential information solutions, announced today that it has entered into a $1.4 million CAD contract with the Canadian Space Agency (CSA) to study the development of a joint Canadian-Italian Hyperspectral Mission.

The joint Canadian-Italian initiative is a collaborative effort between the CSA and ASI (Agenzia Spaziale Italiana) to define a new Hyperspectral Space Mission capable of meeting scientific and operational objectives that stretch beyond what can be achieved using existing technologies. The Italian industrial partner is Alcatel Alenia Space, who has been awarded a similar size contract from ASI.

"We are pleased to be working with the CSA, ASI, and our Italian industrial partner on this Hyperspectral initiative, furthering the next generation of space based information solutions aimed at sustainable resource management and other applications" said Mag Iskander, MDA's Executive Vice President of Space Missions.

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
www.space.gc.ca

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.