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A three-dimensional pulsar magnetosphere model is used to study the geometry of outer magnetospheric gap accelerators, following seminal work of Romani and coworkers. The size of the outer gap is self-consistently limited by pair production from collisions of thermal photons from polar cap heating of backÑow outer gap current with curvature photons emitted by gap-accelerated charged particles. In principle, there could be two topologically disconnected outer gaps. Conditions for local pair production such as local Ðeld line curvature, soft X-ray density, electric Ðeld, etc., support pair production inside an outer gap only between (the radius of the null surface at azimuthal angle /) and r in (/) r lim (/) B 6r in (/ \ (the light cylinder radius). Secondary pairs, on the other hand, are produced almost everywhere 0) > R L outside the outer gap by collisions between curvature photons and synchrotron X-rays emitted by these secondary pairs. These processes produce a wide X-ray fan beam in the outgoing direction and a very narrow beam in the incoming direction for each outer gap. For pulsars with a large magnetic dipole inclination angle, part of the incoming c-ray beam will be absorbed by the stellar magnetic Ðeld. If the surface magnetic Ðeld is dominated by a far o †-center dipole moment (e.g., as in a proposed "" plate tectonic ÏÏ model), gravitational bending of photons from polar cap accelerators and their ultimate conversion into outÑowing eB pairs can result in the quenching of one of these two outer gaps. Various emission morphologies for the pulsar (depending on magnetic inclination angle and viewing angle) are presented. Double-peak light curves with strong bridges are most common. From the three-dimensional structure of the outer gap and its local properties, we calculate phase-resolved spectra of gamma-ray pulsars and apply them to observed spectra of the Crab pulsar.