This report consolidates volunteer angler diary information, collected from a variety of sources over a period of more than forty years, to provide an overview of muskellunge sport fisheries in Ontario. Based on reported angling effort it is obvious that muskellunge are becoming an increasingly popular species. Muskellunge catches were found to be strongly correlated with reported angling effort. Angling success, in terms of catch-per-unit-effort, has improved over the past twenty-five years and Ontario waters now provide some of the highest quality muskellunge fisheries in North America. Muskellunge in excess of 50 inches are captured from several waters each year. It is expected that the next world record muskellunge will be angled from somewhere in Ontario. Voluntary release rates of muskellunge among muskellunge anglers have also increased over the past two decades to the point where approximately 98% of all angled muskellunge are now released after capture. Overall, Ontario’s muskellunge fisheries appear to be stable and sustainable. This can be attributed to an increase in the catch-and-release ethic as well as new minimum size limit regulations. Volunteer angler diary programs should continue to be used to monitor the status of Ontario’s muskellunge fisheries in the future.