  The Advanced Gamma-ray Imaging System (AGIS) is a next-generation
ground-based gamma-ray observatory being planned in the U.S. The anticipated
sensitivity of AGIS is about one order of magnitude better than the sensitivity
of current observatories, allowing it to measure gammaray emmission from a
large number of Galactic and extra-galactic sources. We present here results of
simulation studies of various possible designs for AGIS. The primary
characteristics of the array performance - collecting area, angular resolution,
background rejection, and sensitivity - are discussed.
