Port wine stains (PWS) are congenital vascular malformations for which lasers are the treatment of choice. This article reviews laser optics in relation to PWS treatment and discusses the major laser and light source systems, including the fiashlamp-pumped pulsed dye laser (FLPDL), cryogen spray cooling in combination with the FLPDL, the potassium titanyl phosphate (KTP) laser and the intense pulsed light source, currently utilised for this procedure. Future opportunities for therapeutic improvement are also considered.