In this video, Dr. Joseph Dayan performs a Diagonal Upper Gracilis (DUG) Flap dissection on a young woman for delayed breast reconstruction. The DUG flap is oriented parallel to Langer's lines, allowing for a straight line closure along the line of least tension and can be rapidly elevated in the supine position. This results in a low risk of potential wound healing complications and a wider flap dimension compared to transversely-oriented flaps such as the TUG or PAP. In addition, the orientation of the donor site closure contours the thigh, minimizing the risk of a "shark bite" appearance. The DUG flap is particularly useful in thin patients such as this one or patients who do not have a DIEP flap donor site option. Chapters of this video include DUG flap markings, flap elevation, recipient vessel preparation, anastomosis, and flap inset.