Complex trauma to the forearm often involves significant damage to or loss of bone, muscle, skin, tendons, and neurovascular structures. Treatment focuses on regaining long-term hand function, which is best achieved by combining plastic and orthopedic surgical expertise in a team that includes experienced upper arm rehabilitation therapists. The reconstruction goal is to restore a level of hand function that allows the patient to incorporate the injured hand back into daily activities. We define complex defects as those involving significant segmental loss of one or more tissue types. This article provides a framework by which these often formidable and overwhelming injuries can be approached, and discusses some of the surgical options used to reconstruct complex defects of the forearm.