Pollution in fish habitats can have economic effects on three groups: (1) commercial users and consumers; (2) recreationalists; and (3) nonusers. In commercial fisheries, the economic costs of pollution in the fishery habitats derive from lower production, or consumer perception of reduced fish quality, or both. The economic loss will depend on many factors, including the response of fish stocks to pollutants, the responsiveness of consumers to price changes, and the magnitude of the perceived change in quality of the fish products. Recreational losses due to pollution are manifest in the catch rates of recreational fishers. Additionally, the potential exists for anglers to value fish less if they are afraid to consume the fish they catch because of the quality of the habitat. For any given fishing trip, a decrease in catch rates or reduced take-home catch because of pollution results in fewer benefits to the angler from the experience. Also, people may substitute less pleasurable activities for trips to catch fish from polluted waters. Some individuals may be willing to pay something to avoid pollution in fishery habitats even if they do not intend to go recreational fishing or to consume the fish. The principle way to measure these “nonuse” values is through direct questioning (contingent valuation) rather than by observing market behavior.