Charles Whitney Gilmore (1874-1945), affectionately known as “Charlie” to his colleagues, was one of the last major figures of America’s “Golden Age” of dinosaur hunting. It is largely due to his efforts that the Department of Paleobiology is now home to one of the premier collections of dinosaurs and other fossil reptiles in the United States. Early in his career Gilmore commenced scientific studies of dinosaurs and many other groups of extinct reptiles, starting with the rich material from the Marsh Collection. His monographs on the skeletal structure of the armored Stegosaurus (1914), the predatory dinosaurs Allosaurus and Ceratosaurus (1920), and the sauropod Apatosaurus (1936) remain essential references for any serious student of dinosaurs. Working at a time when there were few professional vertebrate paleontologists, Gilmore also received invitations from other institutions, including the Carnegie Museum and the American Museum of Natural History, to study and publish on important specimens of dinosaurs and other fossil reptiles from their respective collections. Many important papers, including the first monograph on early Late Cretaceous dinosaurs from Inner Mongolia (China), resulted from these “extramural” research efforts. The collections of fossil reptiles in the Division of Vertebrate Paleontology offer eloquent testimony of Gilmore’s devotion and efforts and will continue to be an unparalleled resource for research and exhibition.