William Krehm (born November 23, 1913) is a Canadian author, journalist, political activist and real estate developer. He was a prominent Trotskyist activist in the 1930s and went to Spain where he participated in the Spanish Civil War. In the 1980s he co-founded the Committee on Monetary and Economic Reform (COMER) in the 1980s and has continued as the group's principal leader to the present day.
Krehm was born in Toronto to JewishRussian and Urkainian immigrant parents. He graduated from the University of Toronto. A talented violinist, he was sent to Chicago by his parents to study music in the 1920s. He then moved to New York City where he worked selling hats. After the , he became interested in Marxism.
Returning to Toronto, he studied mathematics at the University of Toronto for two years before dropping out.
By 1932, Krehm had become a Trotskyist, recruited to the movement by Albert Glotzer and joined the nascent Canadian Trostksyist movement in Toronto, which was a branch of the US-based Communist League of America. Krehm led a faction in opposition to Canadian Trotskyist leader Maurice Spector and dropped in and out of the organization, eventually moving to Montreal and becoming leader of the party branch there. In 1934, Krehm and his followers, along with B. J. Field and his followers in the United States, left the CLA to form the Organizing Committee for a Revolutionary Workers Party (later known as the League for a Revolutionary Party, and colloquially as the "Fieldites"), and affiliated with the international organization known as the International Bureau of Revolutionary Socialist Parties or London Bureau. Krehm became leader of the Canadian group and editor of the its newspaper Workers' Voice