The opposition leader is the opposition's counterpart to the prime minister. He or she is expected to be ready to form a new government if the incumbent government is unable to continue in office. This typically occurs when the opposition wins a federal election, after which the opposition leader is appointed prime minister. However, the opposition leader may also be called upon to form government if the incumbent government loses the confidence of the House (most recently in 1941) or that of the governor-general (most recently in 1975).