Permant hair removal is not possible with any current laser hair removal systems at this time. Since hair is in three phases of growth, the laser hair removal only works on hair that is actively growing. Hair that is in the resting phase will not be affected by laser hair removal. Only follicles with actively growing hairs are effectively treated with the hair removal system and that is why multiple treatments are required. Any laser or IPL hair removal system has similar efficacies; some may require more treatments than others and some can only be used on certain skin colors. The ND:YAG hair removal system can be used on patients of all skin colors or types without causing hypopigmentation or loss of pigment. Most systems require 4 to 6 treatments depending upon hair density and the rapidity with the hair is growing. All with result in permanent hair loss or reduction; however, they all require touch-up treatments six months to a year later as new cycles of hair growth occur. I hope this information helps.