Observers have often noted how policy-makers, in the course of interaction among themselves and in their day-to-day dealing with a public problem, tend to develop a common way of looking at and dealing with problem. This suggests that policy subsystems play a significant role in the process of policy formulation. For example, has argued that the nature of the policy subsystem responsible for policy formulation is an important element in the analysis of policy change as coalition members mediate the exchange of interests and ideas in public policy-making. More specifically, analysts have suggested that the ‘cohesiveness’ or ‘clolsedness’ of policy subsystems is an important factor affecting the propensity for new or innovative policy solutions to emerge from the policy formulation process put it, ‘to know the actor constellation is to know the parameters determining the choices among the substantive policy options.