This paper summarizes a framework for understanding freshwater trout fishermen and how such a framework can be used in coldwater fishery management. It is based on a sociological study of "angler specialization" and how it relates to fisherman behavior, attitudes, and fishery management preferences. Angler specialization refers to a continuum of fishermen types from the beginning fisherman to the advanced specialist, reflected by such factors as amount of participation, gear and equipment used, and commitment to the sport. Anglers identified themselves according to the independent variable of specialization level (occasional, generalist, specialist) and significant differences (P ≤: .05) were found in dependent variable categories of behavior, attitudes about fishing, and management philosophy. Angler groups differed according to amount of fishing activity, gear use, water preferences, and resource management philosophy; and the specialization framework was found to be a helpful tool for describing fishing effort. It can be used in standard creel surveys to provide additional information to formulate and evaluate management strategies. Data on the diversity among trout anglers can be blended with biological, physical, and economic information to both conserve the fishery resource and provide improved fishing opportunities.