Dr. Peter H. Raven is the director of the Missouri Botanical Garden and Engelmann professor of botany at Washington University at St. Louis. He oversees the garden’s internationally recognized research program in tropical botany, one of the world’s most active in the conservation and study of imperiled tropical habitats. Professor Raven’s botanical work and research in the area of tropical conservation have earned him numerous awards and honors, including a MacArthur Fellowship. He has written over 17 textbooks and more than 400 articles, and he is a member of the National Academy of Science and the National Research Council.