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Although the acute toxicity test has been rightly criticized for a variety of technical reasons that are beyond the scope of the present discussion, the principal criticism probably stems from inferential uses of acute toxicity data beyond their limitations, and out of context from other measures necessary for hazard evaluation. Unfor- tunately, that is the way things are in the real world, because acute toxicity measure- ments may be the only aquatic effects data available for many chemicals, and then for only a fraction of the thousands of chemicals that have been identified as having potential for escape into the environment. Ideally, evaluators of potential chemical hazards to the environment would prefer a plethora of additional measurements con- cerning possible effects on growth, reproduction, pathology, biochemistry, popu- lations of aquatic organisms, and ecological relationships. Frankly, the U.S. scientific community does not have the time, research facilities, trained personnel, experimental animals, nor financial resources to provide the additional data needed for "com- fortable" predictions of the possible environmental effects of a broad spectrum of chemical contaminants. What is needed is a strategy for concentrating limited scien- tific resources on those chemicals most likely to have adverse impacts on aquatic systems. Similarly, a chemical-analytical strategy is needed for a more comprehensive approach to the detection, identification, and analysis of a broader spectrum of chem- icals in selected environmental compartments. Such strategies would probably not be foolproof and would be different for aquatic ecosystems than for terrestrial eco- systems. On the brighter side, where rationales exist for targeting research priorities on specific chemicals, toxicological evaluations beyond the acute test are being empha- sized. Strategies are being developed to improve quality control in test methods, and to develop schemes for deciding depth of environmental effects testing, particularly under the aegis of the American Society of Testing and Materials and the American Institute of Biological Sciences. It is interesting to note, however, that nearly all such strategies and methods include acute toxicity measurements in the early phases of evaluating effects of pesticides and other potentially toxic materials on aquatic organ- isms. Unless other techniques can be shown to be equally or more meaningful to aquatic toxicologists, the acute toxicity test is here to stay. For a broader discussion of the methods, uses, and limitations of acute toxicity tests and data, the reader is advised to examine three review papers by Sprague (1969, 1970, 1971), and documents prepared by two groups: the Committee on Methods for Toxicity Tests with Aquatic Organisms (1975); and the Aquatic Hazards of Pesticides Task Group (American Insti- tute of Biological Sciences 1978b). Richard A. Schoettger, Director Columbia National Fisheries Research Laboratory iv