The Conference on the Ecotoxicity of Heavy Metals and Organohalogen Com pounds was held under the auspices of the NATO Science Committee as part of its continuing effort to promote the useful progress of science through international cooperation. Science Committee Conferences are deliberately designed to focus atten tion on unsolved problems, with invited participants providing a variety of complementary expertise. Through intensive group discussion they seek to reach a consensus on assessments and recommendations for future research emphases, which it is hoped will be of value to the larger...