/ In Finland, small forest lakes and rivers in the northern part of the country are more sensitive to acidic deposition than other Finnish waters. In some lakes, acid-sensitive fish populations have declined. A nationwide survey of fishers showed that, at present, the number of fishers whose primary fishing waters are affected by airborne acidification is negligible compared to the estimated total number of adult fishers (1.1 million). The proportion of the fishers who mainly fish in water types sensitive to airborne acidification is considerable, 3% for the rivers in northern Finland and 21% for small forest lakes. There is general concern among fishers about the effects of acidification. Changes in the fishing waters are attributed to acidification by 5-10% of the fishers, although in most cases other information about the fishing waters rules out acidification as an explanation for the changes. Among those who fish in sensitive types of waters, a willingness to mitigate potential damages was reported by approximately one third of all fishers. Clear differences in the willingness to rehabilitate the fishery were observed in relation to the importance of fishing as a spare time activity and the distance between the fishing waters and a home or summer cottage.Acidification has a clear impact on fish stocks in affected waters. Critical pH and alnminum levels have been identified for a number of fish species, and the geographical extent of damages to fish populations has been surveyed in many countries (see Baker and Schofield 1985, Henriksen and others 1989, Tuunainen and others 1991. Less emphasis has been put on the impact on fisheries. In most cases, only aggregate potential losses of catches have been estimated. The aggregate loss of total catch is, however, not an appropriate measure of the effects on recreational fisheries. The catch is only one of the dimensions of the demand in recreational fisheries (e.g., Bryan 1979, Fedler and Ditton 1986, Leinonen and HildEn 1991, and the size of the catch does not necessarily reflect the social or economic importance of the recreational fishery (Navrud 1991).The critical loads of acidifying substances in small and sensitive watercourses are exceeded in all parts of Finland (Forsius 1992). The surveys of acidification