Activist student organization in the U.S. Founded at the University of Michigan in 1960, its chapters were initially principally involved in the civil rights movement .
Its "Port Huron Statement" of principles (1962) called for a new "participatory democracy." After organizing a national march in 1965 to protest U.S. involvement in the Vietnam War , it became more militant, organizing student sit-ins to protest universities' participation in defense-related research. By 1969 the SDS had split into factions; the most notorious was the terrorist-oriented Weathermen, or Weather Underground. By the mid-1970s the group was defunct.