We report the results of pulp reconstruction with a new heterodigital reverse flow island flap. A dorsolateral flap from the middle phalanx, based on the digital artery is raised from the adjacent uninjured finger. The common digital artery, between the injured finger and the donor finger, is ligated and transected just before its bifurcation. The two converging branches of the digital arteries can be entirely mobilized as a continuous vascular pedicle for the flap. Thus the vascularization is now supplied by reverse flow through the proximal transverse digital palmar arch of the injured finger. To provide sensation the dorsal branch of the proper digital nerve from the donor finger can be included in the flap. Six reverse heterodigital island flaps were used in patients. In five patients the flap was used for pulp reconstruction and in one case for covering a dorsal digital defect. In one case mild venous congestion occurred. Good skin coverage with supple and well-vascularized skin was obtained in each patient. The static two-point discrimination over the flap was between 6 and 15 mm. This new procedure is indicated for extensive pulp defects in fingers in which reconstruction cannot be done using other flaps and as an alternative to microsurgical reconstruction.