The major factor limiting reconstruction of major postmastectomy deformities (especially after a radical mastectomy, such as that of Halsted) has been the lack of a satisfactory flap operation. The latissimus dorsal flap fills this need, as it allows a safe one-stage breast reconstruction, with an improved aesthetic result. It should be considered whenever insufficient chest wall skin remains for a satisfactory reconstruction. The author's technique for performing this flap operation is described, having evolved from cadaver dissections and eight clinical cases.