Saponins are glycosides of triterpenes, steroids or steroidal alkaloids. They can be found in plants and marine organisms. Very diverse biological activities are ascribed to saponins and they play important roles in food, animal feedstuffs, and pharmaceutical properties. This volume provides a selection of work on saponins presented at a symposium in Pulawy, Poland, in 1999. Many different aspects are treated: analysis, separation, biological activities, relevant use in human and animal nutrition, and ecological significance.