David Wilken began representing injured workers in 1990 as a member of the Advocates for Injured Workers' (AIW) student legal clinic, serving for six years as the division's primary legal supervisor. He has worked for Injured Workers’ Consultants, the Office of the Worker Adviser and (from 1994 to 2009) the Industrial Accident Victims Group of Ontario (IAVGO). He currently works for the Building Trades Workers’ Services, a non-profit association of local unions.