March 28, 2011

MDA to provide operations and maintenance support to DND's Canadian Space Surveillance System

Richmond, B. C. - MacDonald, Dettwiler and Associates Ltd. (TSX:MDA), a provider of essential information solutions, announced today that it has received a contract worth $11.7 million (CAD) from Canada's Department of National Defence (DND) to operate and maintain the Sapphire System for five years following system commissioning. Developed, built and operated by MDA, the Sapphire System is an information solution that will routinely monitor thousands of space objects 24/7 and provide data on several hundred objects of interest every day within hours of observation.

Space Situational Awareness is becoming an increasingly important factor for Canada. For example, early warning of potential collisions can provide satellite operators opportunity to perform collision-avoidance maneuvers when necessary. The Sapphire System will be the largest part of the Canadian Space Surveillance System, and will become the newest space-based sensor of the Space Surveillance Network (SSN), following its launch in late 2011.

MDA's responsibilities include relaying assigned taskings from DND to the satellite, processing the collected information, and sending the data to the Sensor System Operations Centre (SSOC) operated by DND at the 22 Wing in North Bay, Ontario. Upon receipt of the processed data, the SSOC will correlate, identify, archive and transmit the information to the United States' Joint Space Operations Center (JSpOC).

The U.S. JSpOC provides space situational awareness information to at least 134 countries through the SSN consisting of a network of approximately 25 ground and space-based sensors around the world.

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 information solutions, ranging from complex operational systems, to tailored information services, to electronic information products.

The Company's common shares trade on the Toronto Stock Exchange under the symbol (TSX: MDA).

Related Websites:
www.mdacorporation.com
www.cfd-cdf.forces.gc.ca/sites/page-eng.asp?page=6250
http://www.au.af.mil/au/awc/awcgate/usspc-fs/space.htm

Forward-Looking Statements

This release contains forward-looking statements and information, which reflect the current view of MacDonald, Dettwiler and Associates Ltd. ("MDA" or the "Company") with respect to future events and financial performance. The forward-looking statements in this regard include statements regarding the award of a government contract. Any such forward-looking statements are based on MDA's current expectations, estimates, projections and assumptions in light of its experience and its perception of historical trends. The factors and assumptions underlying the forward-looking statements in this release include contracts with any government agency not being terminated. Any such forward-looking statements are subject to a number of risks and uncertainties that could cause actual results to differ materially from current expectations. MDA cautions readers that should certain risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary significantly from those expected. The risks that could cause actual results to differ from current expectations include changes in government priorities, funding levels, contracts and regulations; failure of third parties and subcontractors; satellite failure; and failure of systems to meet performance requirements

For additional information with respect to certain of these risks or factors, plus additional risks or factors, reference should be made to the Company's continuous disclosure materials filed from time to time with Canadian securities regulatory authorities, which are available online at www.sedar.com or on the Company's website at www.mdacorporation.com.

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