The International Socialists (1968–1986) was a Third Camp Trotskyist group in the United States.
The roots of the IS went back to the fall of 1964 when the Berkeley locals of the SP-SDF and YPSL left with 16 members to found the Independent Socialist Club led by Hal Draper and Joel Geier. At first it consisted mainly of ex-Independent Socialist League members who had disagreed with the decision to merge the ISL into the Socialist Party-Social Democratic Federation in 1958 and had become uncomfortable with the positions taken by Max Shachtman and the Realignment Caucus within the party, i.e. entry into the Democratic Party, and an orientation toward the established union leadership and integrationist forces within the Civil Rights Movement. The new group wished to revive the tendency represented by the ISL and the third camp. While still basing its ideas on the literature of the ISL, as the new organization grew through the 1960s, the proportion of former members of the ISL declined, until they were a small handful by 1970.
The following year a second ISC was founded in Berkeley (one on campus, one in town) and another in New York. In September 1967 a conference was held in New York and the clubs were federated under the umbrella Independent Socialist Clubs of America. A quarterly, Independent Socialist or I.S. had begun in early 1967 and became the organ of the new group.
The group worked within the CORE, the Berkeley Free Speech Movement and help initiate the California Peace and Freedom Party, which it saw as a form of "independent political action...leading eventually, or hoping to crystallize the development of a Workers party". The movement recruited many members from its work in the PFP and among Students for a Democratic Society. When the SDS imploded in 1969 many of its members joined the Independent Socialists, including the Revolutionary Socialist Caucus, and significant parts of the SDS chapters at the University of Chicago, University of Michigan, CCNY, and Madison. The Revolutionary Workers Committee at Detroit also joined. With all of these additions it was decided that a national organization should be created, more centralized than the former federation of autonomous clubs. Thus "International Socialist" was formed at a convention in September 1969.