The Communist Unity Group (CUG) was a small communist organisation in the United Kingdom. The origins of the group lay in the Socialist Labour Party (SLP). The SLP was a De Leonist group, but in support of the October Revolution, it decided to participate in unity negotiations with the other British communist groups – principally the British Socialist Party (BSP) and the Workers Socialist Federation (WSF). To this end, it formed a Unity Committee in January 1919. This committee included many prominent members of the SLP: Tom Bell, Arthur McManus, J. T. Murphy and William Paul, all of them proponents of a united communist party.