Editor: Cipriano Marin. Published by: Starlight Initiative (2008). With the support of: UNESCO-MaB, World Heritage Center, CIE, IAC, IAU (International Astronomical Union). A Starlight Reserve is a site where a commitment to defend the night sky quality and the access to starlight has been established. This document deals with the dimensions of the Starlight Reserve concept, the categories of Starlight Reserves, their zonation, and it contains the guidelines and recommendations for outdoor lighting and sky protection.