The study group consists of patients undergoing bilateral cosmetic breast surgery at BMI Edgbaston and Priory hospitals and Spire Parkway and Southbank hospitals in Birmingham and Worcester. If a patient consents to being involved in the research, they will have one breast randomised to receiving a pec block and the contralateral (opposite) breast will receive the same amount of local anaesthetic placed in the breast pocket in a non-targeted fashion. The patients and researcher will be blinded as to the allocation. Patients will complete a verbal numeric pain score for each breast at set intervals until they are discharged.In addition, the investigators will specifically ask which breast is the most painful at each time point.