  We outline the science motivation for SGSO, the Southern Gamma-Ray Survey
Observatory. SGSO will be a next-generation wide field-of-view gamma-ray survey
instrument, sensitive to gamma-rays in the energy range from 100 GeV to
hundreds of TeV. Its science topics include unveiling galactic and
extragalactic particle accelerators, monitoring the transient sky at very high
energies, probing particle physics beyond the Standard Model, and the
characterization of the cosmic ray flux. SGSO will consist of an air shower
detector array, located in South America. Due to its location and large field
of view, SGSO will be complementary to other current and planned gamma-ray
observatories such as HAWC, LHAASO, and CTA.
