MDA's First Quarter 2010 results conference call alert and Annual General Meeting

Richmond, B.C. - MacDonald, Dettwiler and Associates Ltd. (TSX: MDA), a provider of essential information solutions, plans to release its First Quarter 2010 financial results at 4:30 p.m. EDT (1:30 p.m. PDT) on May 5, 2010.

Daniel Friedmann, president and CEO, and Anil Wiresekara, executive vice president and CFO, will host an earnings conference call that day, reviewing strategic progress in the past 12 months, and the First Quarter results, followed by a question and answer session. The call is scheduled to begin promptly at 5:30 p.m. EDT (2:30 p.m. PDT).

To participate in the conference call, please call the conference line approximately five minutes prior to the commencement of the call.

Conference Call Dial-In Numbers:
US/Canada: 1-888-231-8191
International: 1-647-427-7450

Instant Replay
Toll Free: 1-800-642-1687
Toronto: 1-416-849-0833
Pass Code: 66334682

Replay available:
May 5, 2010 5:30 p.m. PDT, 8:30 p.m. EDT to
May 12, 2010 8:59 p.m. PDT, 11:59 p.m. EDT

The conference call will also be Webcast live and then archived at: http://www.mdacorporation.com/corporate/investor/events.cfm

MDA will also be holding its Annual General Meeting at 1:30 p.m. PDT on May 5, 2010 at its Corporate Head Office, 13800 Commerce Parkway, Richmond, B.C.

Agenda for May 5, 2010:

• 4:30 p.m. EDT / 1:30 p.m. PDT – First Quarter 2010 financial results released

• 1:30 p.m. PDT – Annual General Meeting (no participation via conference call)

• 5:30 p.m. EDT / 2:30 p.m. PDT – First Quarter 2010 financial results conference call

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

Forward-Looking Statement

This release and the associated conference call and webcast, which includes the date of the Annual General Meeting, a business update, first quarter 2010 financial review and question and answer session, may contain certain forward-looking statements and information, which reflect the current view of MacDonald, Dettwiler and Associates Ltd. (“MDA”) with respect to future events and financial performance. Forward-looking statements generally can be identified by the use of forward-looking terminology such as "may", "will", "expect", "intend", "anticipate", "plan", "foresee", "believe" or “continue” or the negatives of such terms or variations of them or similar terminology. Any such forward-looking statements are based on MDA's current expectations, estimates, projections and assumptions made in light of its experience and its perception of historical trends. 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. You are referred to the risk factors described in MDA's most recent annual Management's Discussion and Analysis, Annual Information Form and other documents on file with the Canadian securities regulatory authorities, available online at www.sedar.com or www.mdacorporation.com. Any forward-looking statements and information contained in this release and the associated conference call and webcast represent MDA’s views only as of today’s date. MDA disclaims any intention or obligation to update or review any forward-looking statements, whether as a result of new information, future events or otherwise, other than as required by law, rule or regulation. You should not place undue reliance on forward-looking statements.

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