The Economic Policy Institute, Washington, DC

EPI is one of the most respected liberal policy institutes in the United States. They publish research and opinion pieces on the labor market, with a focus on improving the welfare of low and middle-income families. [Note: Do not confuse this institute with the anti-living wage public relations effort, the "Employment Policies Institute." For more information on this group, see: "Employment Policies Institute: Public Relations Nonprofits".]

Interview:
Jared Bernstein -- senior economist

Links:
EPI Living Wage Issue Guide -- a good overview of the issue and (supportive) economic research behind the living wage movement.
"Making a Living: How the living wage movement has prevailed" -- an article by Jared Bernstein of EPI (interviewed here) on the successes of the living wage movement.