 Thus, the authors propose the first, randomized, controlled clinical trial of liposomal bupivacaine for postoperative pain management following tissue expander and implant based breast reconstruction. Patients will be stratified into two study groups. Patients in the Group 1 Bupivacaine will be treated intraoperatively with injections of 0.5 bupivacaine and epinephrine 1:200,000, with 50 mg delivered to perform a field block of each pocket. This is the current standard of care. Patients in the Group 2 Liposomal Bupivacaine will be treated intraoperatively with injections of 1.33 liposomal bupivacaine, with 133 mg delivered to perform a field block of each breast pocket. This is the experimental intervention. Postoperatively, the investigators will assess pain levels, opioid consumption, opioid related adverse events, length of stay, and satisfaction. 