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Besides, vectors derived from AAVs are currently the most promising vehicles for gene delivery to the neural retina. More importantly, subretinal administration of AAVs has been proved to be safe and effective in patients in a number of clinical trials supporting the clinical relevance of this vector. The safety aspects of AAV as a vector are further strengthened by the great versatility of AAV as a vector platform providing many opportunities to engineer this virus to suit particular applications. As there are a large number of naturally occurring AAVs with unique transduction characteristics useful for targeting different cell types, the applications of AAVs grew rapidly in the retina. Sub-retinally delivered naturally occurring AAV serotypes are able to deliver genes to diverse cell types including epithelium, glia, and many types of neurons. This continuous and creative development of AAV vectors provided opportunities to overcome existing challenges in retinal gene therapy.