User summary: This sourcebook is a compilation and standardization of commercially published (primarily "canonical") materials dealing with the Astral plane. Getting to and from the plane, travel in the plane, and numerous other aspects of the Astral plane are discussed. The intent is to present a single source of codified and combined information that is fully compliant with (in fact, fully derived from) the official rules of the game. Sources are enumerated, and derive from the Advanced Dungeons & Dragons (1st Edition), except for Planescape Campaign Setting.