Patients who require a removal of a breast (mastectomy) for breast cancer or future risk reduction often have immediate breast reconstruction (IBR). This can be performed using either an implant or the patient's own body fat to recreate the breast shape. Patients can find it difficult to imagine their own post-surgery appearance. Using 3D surface imaging (3D-SI) can change a patient's pictures to show them how they might look after surgery, known as a simulation. Some patients may find 3D-SI and simulation gives them confidence in their expectations and others may not feel it helps much. This study will investigate the following 3 questions: 1. Whether 3D-SI and simulation can improve patient confidence about their likely post-surgery appearance 2. Whether 3D-SI measurement of breast shape helps in surgical planning and reduces the need for later adjustment surgery to improve symmetry, especially in patients having a mastectomy on one side only 3. How much radiotherapy changes breast reconstructions over time using 3D- SI to objectively measure this. For this study the follow up for some women who do and some who do not have radiotherapy after breast reconstruction. 3D surface imaging may improve surgeon understanding of breast shape, prior to surgery. In cases where there is a high risk of breast cancer recurrence patients are offered radiotherapy to the breast, either before or after surgery. Radiotherapy has a negative impact on the reconstructed breast, and may cause it to shrink and change position but the effect of radiotherapy has never been accurately quantified. This study will be investigating the following: 1. Whether 3D-SI measurement of breast shape helps in surgical planning and reduces the need for later adjustment surgery to improve symmetry, especially in patients having a mastectomy on one side only 2. How much radiotherapy changes breast reconstructions over time using 3D- SI to objectively measure this. For this study the follow up some women who do and some who do not have radiotherapy after breast reconstruction.