That depends on the extent of the areas being treated, the volume of Juvederm Voluma being used and also the complexity of the treatment. Simple injections might take only 15 or 20 minutes, but treatment can require considerably more time depending on what is being treated. For example full face sculpting may require using more of an artist's pallete approach with the use of both needles and the European micro cannula technique and we sometimes need to blend the Voluma with additional lidocaine to customize treatment for non-cheek areas. We may also use other forms of Juvederm such as Juvederm Ultra or Ultra Plus to treat residual smile lines or furrows (note that by lifting the cheek, Voluma often reduces or eliminates the need to treat nasolabial or nose-to-lip folds and smile lines). So the more complete and creative the treatment the more treatment time is required... More on our website...