For Immediate Release: July 10, 2007

U.S. AIR FORCE TO CONDUCT EXTENSIVE ASSESSMENT OF RADARSAT-2 CAPABILITIES

Richmond, B.C. - MacDonald, Dettwiler and Associates Ltd. (TSX: MDA), a provider of essential information solutions,announced today that it has been selected and authorized to start work on a US$9.5 million contract to assist the U.S. Air Force in an extensive evaluation of RADARSAT-2 capabilities. Under the 9-month contract, MDA is to demonstrate the applicability of RADARSAT-2 data to a wide range of current and future defence-related requirements, including maritime surveillance and intelligence applications. In addition, the assessment is to address the potential to build a clone satellite flying in tandem with RADARSAT-2, which would open up a wider set of applications such as the creation of a global high-resolution terrain map.

MDA president and CEO, Daniel Friedmann said: "This is an important milestone in furthering our relationship with the U.S. Air Force. This assessment of the applicability of RADARSAT-2 information positions us to grow in the U.S. surveillance and intelligence market through the provision of essential information."

MDA's contract is with the Canadian Commercial Corporation (CCC), who is acting as the international contracting agency between MDA and the U. S. Air Force. CCC is a Government of Canada Crown corporation, helping foreign buyers obtain goods from Canada and facilitating over $1.2 billion in exports each year.

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

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.