This article on intra-articular fractures of the basilar joint of the thumb discusses the biomechanical and treatment complexities of fractures involving the thumb carpometacarpal joint. This review focuses on the treatment of thumb carpometacarpal fractures and dislocations, consolidating current philosophy and rationale regarding operative and nonoperative treatment. Treatment recommendations are based upon principles established in previous clinical and biomechanical studies emphasizing fracture-specific modalities. Emphasis is placed on maintenance of articular congruity, fracture stability, early motion, and maximum return of function.