Adjuvant radiation therapy for locally advanced breast cancer decreases local recurrence and improves survival. Immediate autologous breast reconstruction before postmastectomy irradiation is highly controversial. However, it is presently unknown whether there exist differences in the durability of various autologous flaps (myocutaneous or fasciocutaneous) to the effects of radiation. All patients who underwent autologous breast reconstruction at the authors' institution between July of 2002 and July of 2005 were evaluated retrospectively. Patients who did not complete all stages of their reconstruction at the authors' institution were excluded. Free flap types were analyzed based on postoperative radiation exposure versus no radiation exposure. The authors also analyzed patients who underwent reconstruction in a delayed fashion with prior radiation exposure and assessed overall outcomes for early and late complications and secondary breast procedures. Three hundred sixty-three of 446 flaps (81 percent) were included in the analysis, with the three most common flaps being the free transverse rectus abdominis myocutaneous (TRAM) flap (7.4 percent), the muscle-sparing free TRAM flap (44 percent), and the deep inferior epigastric perforator flap (41 percent). There were no significant differences in early or late complications among the different flap types or radiation categories. Flaps with prior radiation exposure were associated with higher percentages of contralateral symmetry procedures, whereas flaps with postoperative radiation exposure had a lower incidence of ipsilateral revisions. Autologous breast reconstruction can be performed safely regardless of preoperative or postoperative radiation therapy. There are no significant differences in complication rates or number of revisions based on the type of free flap. Therapeutic, III.