Pharmacognosy is the study of medicinal plants and natural products. It originated in the 19th century focusing on the physical description and identification of plant drugs, and has expanded to include the discovery of therapeutic agents from nature, quality control, and intellectual property rights. Key areas of pharmacognosy application now include cancer therapy, nutraceuticals, herbal medicine quality standards, appropriate plant identification, and ensuring safety and efficacy of traditional medicines through principles of good practices.