Twenty-six patients are presented who underwent reconstruction of the breast and thorax following mastectomy. A successful result ensued in 96 percent of the patients. Indications for the use of microsurgical composite tissue transplantation in breast reconstruction following mastectomy include. 1. Inability to employ an island latissimus dorsi musculocutaneous flap 2. Previous failure of an island latissimus dorsi musculocutaneous flap 3. The restoration of form and contour with minimal secondary donor deformity The present series includes 12 patients who underwent reconstruction utilizing the vascularized groin flap and 14 utilizing the contralateral latissimus dorsi musculocutaneous flap. The advantages and disadvantages of the different donor tissues are presented and contrasted with other vascularized donor tissue also employed in breast reconstruction following mastectomy. Technical modifications correlating the limitations of the donor tissue to the complexities of the recipient site and contributing to successful transplantation are detailed. The authors wish to emphasize that microsurgical composite tissue transplantation for reconstruction of the breast following mastectomy has applicability in only a small carefully selected subgroup of patients--approximately 9 percent.