The standard to which clinical trials must conform is called Good Clinical Practice (GCP). GCP is defined as a standard that ensures adequate protection of subjects participating in clinical trials; furthermore, it ensures that all trial activities and data are meticulously documented and reported. The latest GCP guideline was developed by the International Conference on Harmonization (ICH) and was first published in May 1996. This guideline is based on ethical principles that have their origin in the Declaration of Helsinki (1964, last modified in October 2000). Besides GCP, clinical trials must also comply with the local law of the country where the study is being conducted. This book will be an indispensable companion for those conducting clinical trials and should have a fixed place in the library of every investigator and his staff.