Christians on the Left, formerly known as the Christian Socialist Movement (CSM), is a socialist society in the UK. The movement fulfils a need among Christian socialists for an organisation that would be both politically engaged and theologically reflective. Christians on the Left is a member organisation of the International League of Religious Socialists. Members have included Labour leaders John Smith, Tony Blair, Gordon Brown, R. H. Tawney, and Donald Soper. Today, Christians on the Left has over 40 members in the House of Commons and the House of Lords.
As of March 2025, its director is Hannah Rich and its executive committee chair is Anna Dixon MP.