The management of soft-tissue defects of the hand with exposed bone and tendons may be difficult. The posterior interosseous flap is a fasciocutaneous island from the dorsal forearm, based on the posterior interosseous vessels. We have used this flap as a one-stage procedure to cover soft-tissue defects of the hand in 6 patients. It provides excellent cover without sacrificing a major blood vessel such as the radial artery. Although the vascular anatomy of the flap is normally consistent, variations exist. This prevented elevation of 1 of the flaps in our series.