  The sub-millimetre wavelength regime is perhaps the most poorly explored over
large areas of the sky, despite the considerable effort that has been expended
in making deep maps over small regions. As a consequence the properties of the
sub-millimetre sky as a whole, and of rare bright objects in particular,
remains largely unknown. Here we describe a forthcoming survey (the SCUBA-2
``All-Sky'' Survey, or SASSy) designed to address this issue by making a
large-area map of approximately one-fifth of the sky visible from the JCMT
(4800 square degrees) down to a 1 sigma noise level of 30 mJy/beam. This map
forms the pilot for a much larger survey, which will potentially map the
remaining sky visible from the JCMT, with the region also visible to ALMA as a
priority. SASSy has been awarded 500 hours for the 4800 square degree pilot
phase and will commence after the commissioning of SCUBA-2, expected in early
2008.
