Vancouver, BC - MacDonald, Dettwiler and Associates Ltd. ("MDA" or the "Company") (TSX: MDA), a global communications and information company, plans to release its Second Quarter 2017 financial results at 5:00 p.m. PT (8:00 p.m. ET) on Thursday, July 27, 2017.

MDA President and CEO Howard Lance, and Executive Vice President and CFO Anil Wirasekara, will host an earnings conference call on Friday, July 28, 2017, reviewing the Second Quarter results, followed by a question and answer session. The call is scheduled to begin promptly at 6:00 a.m. PT (9:00 a.m. ET).

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:

International: 1-416-764-8688

Toll Free – North America: 1-888-390-0546

Replay:

International: 1-416-764-8677

Toll Free – North America: 1-888-390-0541

Pass Code: 515418#

Replay available:

From Friday, July 28, 2017, 9:00 a.m. PT (12:00 p.m. ET) to

Friday, August 4, 2017, 8:59 pm PT (11:59 p.m. ET)

The conference call will also be Webcast live and then archived at:

http://www.mdacorporation.com/corporate/investor/events

MDA will also be holding its Annual and Special Meeting at 1:00 p.m. PT on Thursday, July 27, 2017 at the Fairmont Waterfront Hotel, MacKenzie Ballroom, 900 Canada Place Way, Vancouver, BC, Canada V6C 3L5.

Agenda for Thursday, July 27 and Friday, July 28, 2017:

1:00 p.m. PT                Annual and Special Meeting (no participation via conference call)

5:00 p.m. PT                Second Quarter 2017 financial results released

6:00 – 7:00 a.m. PT      Second Quarter 2017 financial results conference call and webcast

MDA is a global communications and information company providing operational solutions to commercial and government organizations worldwide.

MDA's business is focused on markets and customers with strong repeat business potential, primarily in the Communications sector and the Surveillance and Intelligence sector. In addition, the Company conducts a significant amount of advanced technology development.

MDA's established global customer base is served by more than 4,800 employees operating from 15 locations in the United States, Canada, and internationally.

The Company's common shares trade on the Toronto Stock Exchange under the symbol "MDA."

Related Websites

www.mdacorporation.com

The above referenced earnings release and the associated conference call and webcast, which will include a business update, second quarter 2017 results and a question and answer session, as well as the Annual and Special Meeting may contain certain forward-looking statements and information, which reflect the current view of MacDonald, Dettwiler and Associates Ltd. (the “Company” or “MDA”) with respect to future events and financial performance. Any such forward-looking statements are based on MDA’s current expectations, estimates, projections and assumptions made in light of its experience and perception of historical trends. Forward-looking statements are subject to risks and uncertainties, many of which are beyond MDA’s control and the effects of which can be difficult to predict. MDA’s actual results of operations could differ materially from historical results or current expectations. You are referred to the risk factors described in above referenced earning release and in MDA’s most recent annual Management’s Discussion and Analysis and Annual Information Form, which are available online under the Company's profile on SEDAR, 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.