Gluteal augmentation fat grafting (GFG, a.k.a. Brazilian butt lift or BBL) involves the large-volume harvest of subcutaneous fat from undesired areas and subsequent large-volume grafting of that fat into the buttocks and thighs to enhance aesthetic contours. This procedure has been reported to have the highest mortality rate of any cosmetic surgical procedure, primarily due to fatal pulmonary fat embolism resulting from intramuscular injection and injury to the inferior gluteal vein. This chapter reviews the anatomy relevant to GFG and safe techniques to minimize risks and discusses the complications and outcomes associated with this procedure.