The position of Opposition House Leader evolved gradually in the 1950s: an opposition M.P. - usually, but not always, the same - would question the Government House Leader regarding the planned business of the House for the coming week. The title became official in 1963.

The function of Opposition House Leader did not fully emerge until the late 1950's, when the Liberals came to Opposition. In the years preceding the 23rd Parliament, when the Conservatives were in Opposition, their most frequent spokesmen as to the business of the House schedule were Donald M. Fleming and Howard C. Green, or the party leader himself.