It's initial cadre were members of the Movement for an Independent Socialist Canada in the labourite New Democratic Party. After the International Socialists were organised they began publishing a paper called Workers Action. In later years this paper was renamed Socialist Worker.
In 1995 the group saw the loss of some of its members, including David MacNally a well known academic, who formed the New Socialist Group.
Like its sister parties it publishes a newspaper called Socialist Worker.