The outer-shelf of the Great Barrier Reef (GBR) can be broadly defined as the region of the continental shelf between the outer-most emergent reefs and the upper limit of the continental slope at ~200m depth. The outer-shelf is exposed to clear, oligotrophic water from the Coral Sea, and is subjected to prevailing wind and wave energy from the ocean - all factors that strongly influence the ecological communities that occur there. The combination of its offshore location and exposure to wind and swell make research on the outer-shelf logistically challenging; consequently, this region remains poorly known compared with the GBR lagoon and inner-shelf. However, the last decade has seen a rapid increase in research focused on both the geology and biology of the outer-shelf, particularly in depths >30m. This research has revealed a diverse range of physical habitats and ecological communities.