Photodynamic therapy is a relatively selective form of treatment for choroidal neovascularization. Unlike standard laser photocoagulation, photodynamic therapy can close choroidal neovascularization with minimal or no detectable damage to surrounding tissues. Therefore, it allows the clinician to treat subfoveal choroidal neovascularization without immediately adversely affecting central visual function. Several dyes for photodynamic therapy have been under various stages of formal clinical investigation. There is now mounting evidence that shows that photodynamic therapy with at least one of these dyes can significantly reduce the risk of visual loss in eyes with subfoveal choroidal neovascularization from age-related macular degeneration. This form of treatment promises to have a major, favorable impact on public health in areas of the world in which age-related macular degeneration is common.