An unusual case is described in which in spite of clinical, scintigraphic and histologic findings strongly supportive of a diagnosis of "hyperacute rejection," recovery of renal function occurred. These findings are in contrast to the current literature in which it is generally accepted that a renal allograft showing neither pertechnetate transit nor hippurate concentration warrants allograft nephrectomy irrespective of the etiology. Scintigraphic evaluation included both dynamic studies after a bolus administration of Tc-99m pertechnetate and serial renogram collections after the intravenous administration of I-131 Hippuran.