Continuing disquiet over the use of animal by-products in livestock nutrition has provided renewed impetus for the greater exploitation of conventional and novel crop plants both as food and as industrial raw materials. However, a major factor restricting the utilisation of such crops in animal nutrition is the presence of a diverse array of toxic substances capable of inducing effects ranging from loss of hair and wool to severe neurological disorders and even death. Significant advances have been made to establish the nature of these compounds and to assess their effects in animals and man. As in other branches of biomedical research, these developments have been achieved through the multidisciplinary efforts of chemists, biochemists, toxicologists, nutritionists and molecular geneticists. This volume reviews current knowledge of toxic substances in crop plants with particular reference to their anti-nutritional effects in animals and man and the potential for detoxification. The distribution and ecological significance of these compounds is also addressed.