Laidler, Harry Wellington (lādˈlər) [key], 1884–1970, American economist and Socialist leader, b. Brooklyn, N.Y., grad. Wesleyan Univ., 1907, Brooklyn Law School, 1910, Ph.D. Columbia, 1914. A founder (1905) and secretary (1910–21) of the Intercollegiate Socialist Society, he was also executive director (1921–57) of its successor organization, the League for Industrial Democracy. From 1920 a director of the National Bureau of Economic Research, he served twice as president (1930–32, 1948–49). Laidler was the Socialist candidate for numerous public offices and served (1940–41) on the New York City council. His writings include Boycotts and the Labor Struggle (1914), A History of Socialist Thought (1927), Concentration of Control in American Industry (1931), Social-Economic Movements (1944), and The History of Socialism (1968).