Coalition, temporary combination of groups or individuals formed to pursue specific objectives through joint action. The term coalition is most often used in connection with political parties. Coalition governments, which are frequently found in multiparty countries, such as France or Italy, may be formed when no single party is strong enough to obtain an electoral majority. The resulting government usually distributes political posts to representatives of all coalition members. In the United States, with its two-party system, coalitions occasionally cut across party lines to deal with special issues in Congress.

In international politics, nations sometimes band together to achieve a common purpose. Such a coalition is likely to occur in a time of crisis, for example, when nations become allies during a war.