The Minister's individual actions affect his or her colleagues and the credit of the whole Ministry. A fundamental political limit to a Minister's powers is the necessary support of the Prime Minister and other colleagues for the Minister's proposals. Ministers also decide collectively for very practical reasons. The responsibilities of one Minister inevitably have implications for other Ministers. In addition to Ministers needing the political support and counsel of their colleagues, policies and programs must be reviewed in relation to each other if they are to be successful.
Ministers share both parliamentary time and the scarce financial resources of the budget.
In sum, both for constitutional and for very practical reasons, Ministers can only fulfill their individual responsibilities by acting in concert. Canadian Cabinet government requires Ministers to be continually seeking consensus upon their goals, policies, programs and even, to the degree the whole Ministry is affected, upon the means of implementing their programs. In fact these principles are also often expressed in law through requirements for approval of ministerial actions by the Governor in Council or the Treasury Board, on matters such as program expenditures, regulations, appointments, management practices and standards of behaviour. The departmental Acts and any other Acts or organizations for which a Minister is responsible, together with the corresponding budgetary Estimates, provide a basic framework of responsibilities. Changes to parliamentary rules have increased both the scope of parliamentary committee inquiry and the number of occasions on which a Minister and his or her officials may be asked to appear.