Precisely how such theory may be derived is, of course, not immediately evident or predict able. However, a few ideas come to mind. First, public administrative theorists must recognize the validity and utility ofeach ofthe approaches discussed here. Perhaps others can be added in the future, but the legitimacy of each of these is beyond question. Consequently, definition of the field of public administration must include a consideration of managerial, political, and legal approaches. Second, it is necessary to rec ognize that each approach may be more or less relevant to different agencies, administrative functions, and policy areas. For example, re lation stresses adjudication and, consequently, probably should not be organized primarily according to the managerial or political approaches. Likewise, overhead operations most clearly fall within the purview of the managerial approach. Distributive policy may be best organized according to the political approach. Much more thought and research must be devoted to these matters before any firm conclusions can be reached. But clearly it is an administrative fallacy to try to treat all agencies and programs under a universal standard. This is one reason why the much vaunted"rational" budgeting techniques of PPBs and zBB failed 66 Third, as heretical as it will sound to some, public administrative theory must make greater use of political theory. As is argued here, the separation of powers goes well be yond the issues of legislative delegation and agency subdelegationit reaches to the core of the leading theories of public administra tion. Finally, attention must be paid to the practical wisdom of the public administrative practitioners whose action is circumscribed by internal considerations of checks, balances, administrative and political pressures gen and erally. Individual public administrators are often called upon to integrate the three approaches to public administration and much can be learned from their experience.