Current patterns of exploitation threaten the commercial future, as well as the biological survival, of many species of medicinal plants. This chapter discusses the global dimensions of this issue and the problems associated with biodiversity loss. Bringing wild-collected species into cultivation is one solution, but this approach has many limitations. Market forces, socioeconomic considerations, and ecologic factors suggest that most medicinal plants will continue to be wild-harvested. As the global market for herbal medicines increases, supply chains and production methods are in a state of flux. Medical practitioners, consumers, and vendors must be well informed so they can use their influence to steer the industry in a direction that promotes environmental stewardship, as well as improved product quality and availability.