8th Conference on Cytochrome P450, Lisbon, Portugal, October 1993. This book aims to promote the new concepts and aspects of cytochrome P450 science more intensively investigated since the previous meetings of the series. It includes original contributions from some of the most distinguished specialists in the area. The first three chapters concern topics on the evolution of cytochrome P450, the diversity of regulatory mechanisms involved in biogenesis and their importance in environment, cancer risk assessment and immunotoxicity. Chapter 4 deals with biotechnology and novel P450 functions, and includes the opening plenary lecture on basic P450 research and applications in drug development. Chapters 5 and 6 present the most recent progress in cytochrome P450 molecular structure and electron flow mechanisms. Finally, chapter 7 is a compilation of selected papers contributed by the participants in the areas of the physico-chemistry and molecular biology of cytochrome P450.