Background: Successful outcomes with the deep inferior epigastric artery perforator (DIEP) flap are heavily dependent on identifying the largest perforators. The purpose of this study was to describe the vascular anatomy (location, size, zones of perfusion, and variations) of the single most dominant deep inferior epigastric artery perforator and to report a clinical series based on this flap. Methods: Eleven abdominal flaps were harvested from fresh adult cadavers, and measurements were combined with clinical measurements from 16 patients. Details such as perforator size, location, type, and zones of perfusion were documented for all flaps and clinical outcomes for all patients. Results: A total of 36 flaps were dissected with an average perforator location within a 3-cm radius of the umbilicus and an average perforator size greater than 1.8 mm. Computed tomographic scans of the cadaver abdominal flaps demonstrated consistent perfusion in zones I and II and half of zones III and IV. Clinical results showed partial flap necrosis in one patient and fat necrosis of less than 5 percent in three patients, all of which occurred in the distal portion of zone III. The deep inferior epigastric artery medial row perforators near the umbilicus were found to be the largest perforators in the entire deep inferior epigastric artery system and abdomen. Conclusions: The single dominant medial row perforator has a maximal vascularity in zones I and II, and less in zones III an IV. The authors recommend that half of zone III and all of zone IV be discarded to avoid the risks of partial flap loss and fat necrosis.