Scientists struggling with the pharmaco- and toxicodynamic interactions of drugs and chemicals will find this book a valuable reference to the relevant theoretical background of this complex field and an indispensible guide to practical, analytical procedures for evaluation of experimental data. A new, straightforward mechanistically based analysis of observed combination effects is backed up by numerous examples as well as by computer-assisted plotting and curve fitting – using popular graphical software systems. The reader thus can gain not only a modern understanding of this complex area but proceed directly to the evaluation of his own dose-response experiments with respect to independent actions, and additive interactions, where appropriate. The meanings of terms and acronyms in the literature, most of them used in this book also, are elucidated by a comprehensive glossary. This book represents a modern, theoretical and practical guide for all scientists dealing with this controversial and complex area of the action and interaction of drugs and chemicals.