One of the fundamental concepts of toxicology is that chemicals act at selective receptors and that such interactions result in phar- macologic responses which, depending on dose, mayor may not result in toxicity. For us to understand how insecticides produce their toxic effects, we must first understand their molecular interactions with their target receptors. With this in mind, we organized a symposium which was given in conjunction with the XVII International Congress of Entomology in Hamburg on August 21, 1984. The goal of this symposium was to bring together researchers with a wide range...