The authors introduce an experimental model of flap prefabrication, the tail artery interpositional loop (TAIL) flap. In this model, an arterial segment from a rat tail is used to create an arteriovenous (A-V) fistula. This fistula is positioned beneath the abdominal skin flap to vascularize the overlying tissue, and a barrier of Silastic sheeting is placed below the fistula to prevent vascular ingrowth from the underlying bed. The efficacy of this new model was tested by investigating the effect of a single topical application of recombinant human VEGF (165). Treatment and control groups each contained 20 animals. In the control group, mean survival skin areas at 1, 2, 3, and 4 weeks were 12.5 percent, 27 percent, 35 percent, and 50 percent, respectively. In the VEGF (165)-treated group, survival rates were 14.8 percent, 37 percent, 48 percent, and 74.3 percent, respectively. Statistically significant differences were noted between the two groups at the 2-week ( p = 0.047), 3-week ( p = 0.048), and 4-week ( p = 0.023) time intervals. The authors conclude that the TAIL flap is a novel and useful animal model to study flap prefabrication.