In the USA, women seeking breast implants for augmentation, revision or reconstruction can choose between saline-filled devices and round, silicone gel-filled devices. Form-stable, highly cohesive silicone gel-filled breast implants are marketed in other countries and are currently under review by the US FDA. Allergan has conducted clinical studies to investigate the safety and effectiveness of its round and anatomical (Style 410) devices for US marketing approval. The most frequently reported complications were reoperation, implant removal with replacement, implant malposition and capsular contracture. The FDA approved the round devices in 2006. The weight of the scientific literature suggests that silicone gel-filled breast implants do not increase a patient’s risk of cancer, autoimmune disease, reproductive effects or suicide. As differently shaped, cohesive breast implants continue to be introduced, breast implant surgery will become more customized to the patient’s biological conditions and desires.