In a two-party system, bipartisan refers to any bill, act, resolution, or any other action of a political body in which both of the major political parties are in agreement. Often, compromises are called bipartisan if they reconcile the desires of both parties from an original version of legislation or other proposal. Failure to attain bipartisan support in such a system can easily lead to gridlock, often angering each other and their constituencies.
Bipartisanship can also be between two or more opposite groups (e.g. liberal and conservative) to agree and determine a plan of action on an urgent matter that is of great importance to their voters. This interpretation brings bipartisanship closer to the more applied notion of postpartisan decision-making; a solution-focused approach that creates a governance model with third-party arbiters used to detect bias.