Hello and thank you for your excellent question. There are many differences between fat grafting and filler. Fat transfer is taken from your own body, meaning that it will not be rejected. It is also permanent, although the amount of grafted fat the remains may vary depending on where it is grafted. With regard to filler, there is no donor site from which the graft is harvested. In addition, there are dozens of filler types on the market, each of which has a specific application (e.g., cheeks versus lips versus eyes). In general, we use fillers for smaller areas (i.e., 1 - 4 cc's), and fat for larger areas (10cc's up to 1000cc's or more for areas like the buttocks). Preoperative visualization and surgical simulation with the Crisalix system may help with your decision. Any treatment plan should be based on a detailed discussion with equal input from both you and your surgeon. Make sure you specifically look at before and after pictures of real patients who have had this surgery performed by your surgeon and evaluate their results. The most important aspect is to find a surgeon you are comfortable with. I recommend that you seek consultation in person with a qualified board-certified plastic surgeon. Good luck! Best, Jon Ver Halen, MD FACS Harvard educated plastic surgeon