In the past 18 months, advances have been made in both therapeutic interventions and diagnostic techniques. Modifications in laser hardware, for example, have provided a new treatment for cutaneous vascular abnormalities. Although lasers have been used in dermatology since the 1960s, they were modifications of industrial or other medical lasers. The argon laser, which has been the standard for treatment of cutaneous vascular abnormalities, is a modification of the ophthalmic retinal photocoagulator. Despite good results in the treatment of port-wine stains (PWS) in adults, up to a 4.3% risk of scarring still exists,1 and results of treatment in adults with pale, immature PWS and in children are generally poor. The argon laser, which emits light predominantly at 488 and 514 nm, achieves some selective absorption in blood vessels but, because its delivery is continuous, nonselective dermal damage also occurs. The theory of selective photothermolysis predicts that by choosing a