In systems with political parties, individual politicians sometimes change party affiliation, with such changes being more common in some systems than others. In parlaimentary systems, such actions are called crossing the floor. Detailed lists of politicians who have changed parties are listed below. Europe *List of British Members of Parliament who crossed the floor The Americas *List of Canadian politicians who have crossed the floor *Party switching in the United States **List of United States Senators who changed parties **List of United States Congressmen who switch parties