She has worked as Director, Public Affairs, Petro-Canada, as Vice President Communications and Marketing at the Canadian Chamber of Commerce and Vice President Marketing and Communications at United Way Ottawa/Centraide Ottawa. Ms. McMahon is currently Principle of her own communications and marketing consultancy – McMahon Communications – where she works with clients on a broad range of reputation management activities: strategic and crisis communications, media, public and community relations, marketing, brand management, event management and speech preparation.

Most recently, following the death of her husband, OPP Sergeant Greg Stobbart -- killed tragically in a cycling collision in June 2006 -- Ms. McMahon has been working to engineer legislative change in Ontario and is leading the development of a provincial, grassroots cycling advocacy organization in Ontario -- the Share the Road Cycling Coalition. In November 2008, Greg’s Law was tabled in the Ontario legislature as part of a larger Road Safety Bill, Bill 126 and it passed on April 22nd, 2009.

The Coalition’s primary goals are encouraging cycling and in particular, promoting safe cycling. Ms. McMahon is a frequent speaker on active transportation, most recently at the 2008 National Bike Summit in Washington, hosted by the League of American Bicyclists, the 2008 National Bike Rally in Maine and the Toronto Bike Summit (2009). She continues to visit a number of jurisdictions in the United States and Europe to study best practices in cycling accommodations, law enforcement approaches, legislative, and education and awareness programs and is currently working on preparing an Active Transportation White Paper for the Provincial Government in Ontario, an outcome of the Ontario Bike Summit (September 21-22) organized by the Coalition.