This is the fourth in a series of papers that detail methods which States have used to protect instream flows. This paper discusses Iowa's efforts to protect instream uses through administrative methods; i.e., the exercise of State government authority in issuing, refusing, and conditioning water use permits. The intended audience for this paper includes individuals concerned with State water plans, State water administration agency personnel, Federal fish and wildlife biologists, water management personnel, and the general public. This paper provides a look at the basic institutional processes in the management of instream uses of water. This paper discusses the basic water law system in Iowa, which is important because any attempt to establish a system of instream flow protection must work within the framework of the law. This paper also provides an analysis of Iowa's governmental decisions about water allocation. The emphasis, however, is on Iowa's stream flow protection program.