This book presents refereed and edited papers from the 6th International Symposium on Poisonous Plants, held in Scotland in August 2001. It covers a range of topics from plant biochemistry to toxic effects in animals (particularly grazing farmed animals) and humans. The contents include the evolution of antinutrients and toxins in plants, biomedical applications of toxins in plants, isolation, identification and effects of plant and fungal toxins and the effect of plant toxins on aversion to plants in animal diets.