Discovery for the advancement of medicine and understanding of life sciences constitutes one of the most powerful ways in which biodiversity can contribute to human society. Bioresources have tremendous potential in providing bioactive compounds for the development of new lead candidates for pharmaceuticals, nutraceuticals, and agrochemicals. Therefore, natural products continue to be an important source of modern drugs in clinical use as an active ingredient, starting material to produce semi-synthetic drugs as well as templates for totally synthetic drugs. The key to success for discovering therapeutic agents from bioresources is based on bioassay-directed isolation techniques. High-throughput screening tests and mechanism-based screening protocols as well as information of folkloric utilization of plants have led to the discovery of lead compounds as drug candidates. Given the current research and development performance associated with the understanding of disease process, there is still a great need for novel compounds with unique mechanisms of action to treat diseases such as cancer, Alzheimer's disease, arthritis, diabetes, etc. The lecture will highlight bioactive compounds arising from the screening of some Turkish plant extracts. Due to human population growth and economic pressure, the loss of the earth's biodiversity is one of the most pressing environmental and development issues today. IUPAC-approved recommendations for global cooperation on sustainable utilization and conservation of biodiversity will also be presented as the dissemination effort of the recommendation. © 2005 IUPAC.