Until recently, human-induced perturbations other than fishing have received little attention in the stock assessment literature, Beginning in the late 1960s, environmental legislation in the United States has directed attention toward assessing the mortality of fish and other living aquatic resources caused by observed (or anticipated) changes in water quality or other habitat features that are related to ongoing (or proposed) human activity. Scientists are being requested not only to devise means to estimate the extent of aquatic impacts related to the causes, but also to devise means to reduce or avoid them. In this paper I review methods that can be used for comparing the population-level effects of mortality in fish populations induced by pollution (and sources with similar effects) to mortality induced by fishing. I also review the types of data needed to use the methods, limitations of the methods, and examples of method applications. Methods reviewed are the equivalent adult, production forgone, reproductive potential (eggs per recruit and spawning stock biomass per recruit), and individual-based. All of the methods reviewed share several common limitations, the foremost being inherent difficulties in estimating survival rates for early life stages of fish. Despite their shortcomings, the methods have been and continue to be useful tools for fishery management.