Scientists struggling with the pharmaco-and toxicodynamic interactions of drugs and chemicals will find this a valuable reference to the relevant theoretical background of a complex field as well as a guide to practical, analytical procedures for the evaluation of experimental data. A mechanistically-based analysis of observed combination effects is backed up by numerous examples as well as computer-assisted plotting and curve fitting, using popular graphical software systems. Readers can proceed directly to the evaluation of their own dose-response experiments with respect to independent actions and additive interactions, where appropriate. The meanings of terms and acronyms are illucidated by a comprehensive glossary.