The life of William G. D'Arcy was unusual in many respects. His research career as a systematic botanist would be considered exceptionally productive even if begun in his twenties, rather than at age 41when most scientists are already in mid-career. A native of western Canada, D'Arcy developed early natural history interests. In college he concentrated on economics, unable to imagine making a living in natural history. In his early career he worked as an economist, and then as an entrepreneur in the British West Indies. In that beautiful locale, a fascination with the local flora gradually attracted more and more of his energy. Deciding on a career change, D'Arcy pursued master's (University of Florida) and doctoral (Washington University) degrees. In each case his thesis treated the nightshade family, Solanaceae, the plant family that remained his life-long passion. During his doctoral work, D'Arcy was exposed to the Missouri Botanical Garden's program in Panamanian floristics. With this field experience and Ph.D. in hand, he was appointed by the Garden to organize the completion of the multi-volume Flora of Panama project. Coordinating a network of collaborators, he accomplished this to a high standard within a decade. Simultaneously, he developed the first computerized database for a large flora. Over the years at Missouri he rose to the rank of Curator and became an internationally recognized expert in the systematics and evolution of the large and economically important nightshade family. By himself, and with numerous collaborators and students, D'Arcy investigated many structural and physiological phenomena impinging on the evolution of the family. He organized scientific meetings, carried out 25 field expeditions, and published about 144 scientific contributions. This volume features a collection of scientific contributions by D'Arcy's friends and colleagues that form a fitting memorial to the life of this influential taxonomist. In addition to Solanaceae, there are contributions on genera of Araceae, Myrtaceae, Rubiaceae, and Rutaceae, from the perspectives of taxonomy, floristics, cytology, and other fields that reflect D'Arcy's broad interests. Thirteen new species are described. In addition, a biography and publication list, as well as lists of taxa described by him and described in his honor, summarize the life and work of this extraordinary botanist.