The laser emits a gentle beam of energy that passes through the skin to the hair follicle, damaging the follicle. The most dramatic results occur for patients with light skin and dark hair, but patients with darker skin can also benefit from the procedure. Hair grows in cycles so the number of treatments required varies with each individual. The laser only affects hair when it is in its early-growth phase. At any time, some hair follicles are dormant. Repeat sessions will treat these follicles when they re-enter the growth phase.