Interosseous membrane (IOM) deficiency results in longitudinal radioulnar instability, and may result in proximal radial migration, increased radiocapitellar contact, limitations in forearm rotation, ulnocarpal instability, and ulna-sided pain. A number of reconstruction methods have been posited-however, few have been implemented in vivo. We describe a 2-bundle method of IOM reconstruction, utilizing flexor digitorum superficialis autograft. This technique has the benefits of utilizing a locally available and robust autograft with minimal donor-site morbidity, obviating the concerns associated with synthetic grafts or bone-patella tendon-bone constructs. It also replicates the nonisometric nature of the native IOM. We also present long-term results of a patient who underwent IOM reconstruction utilizing this method, following a cadaveric feasibility study.