The treatment time can vary considerably depending on the size of the area treated, and the particular technique used. A small area such as the upper lip may take only five minutes, while a larger area like the back or legs may take up to one hour. Since the laser affects only those hairs in the growing stage, and not all hairs will be in this stage at the same time, several treatments will most likely be needed to effectively remove all the hair from one area. Subsequent sessions will be scheduled at least a month apart. By this time you will probably begin to notice the re-growth of hairs that were previously in the resting stage.