The European Commission Directive 91/507/EEC has been enforced since January 1, 1992. It requires that all trials of a clinical development program be performed in compliance with Good Clinical Practice (GCP) guidelines which became effective on July 1, 1991 after approval by the CPMP in July 1990. Good Laboratory Practice (GLP) guidelines originated in the USA in 1978 and have been adopted in general in the OECD guidelines (OECD principles of Good Laboratory Practice, 1983) and in the appropriate national laws and guidelines, e.g., Chemikaliengesetz vom 14.3.1990, Germany. All GLP guidelines unambiguously address "non-clinical laboratory studies", for example, toxicological studies but not studies utilizing human subjects. The impact/non-impact of these guidelines is addressed by the day-to-day work in a clinical pharmacology unit within the pharmaceutical industry.