The Sydney University Molonglo Sky Survey (SUMSS) is carried out at 843MHz with the Molonglo Observatory Synthesis Telescope (MOST) in its upgraded wide-field capability. The survey consists of 4.3x4.3{deg} mosaic images with 45x45''cosec{delta} resolution, covering 8000 square degrees from -30 degrees declination southwards with |b|>10{deg}. The survey resolution and sensitivity (1-sigma noise limit 1mJy) are well-matched to the NRAO VLA Sky Survey (NVSS) so that together NVSS and SUMSS provide a complete survey of the radio sky. The version 2.0 (08-Aug-2007) of the catalogue consists of 210412 radio sources made by fitting elliptical gaussians in 633 SUMSS mosaics to a limiting peak brightness of 6mJy/beam at declination <-50{deg}, and 10mJy/beam at declination >-50{deg}. Positional accuracies are 1-2'' for sources with S_p_>=20mJy/beam, and are always better than 10''. The internal flux density scale is accurate to 3%. Image artefacts have been classified using a decision tree, which correctly identifies and rejects spurious sources in over 96% of cases. See the SUMSS site at http://www.astrop.physics.usyd.edu.au/sumsscat/ for details about all versions of the SUMSS, and an access to the mosaic images. The version 2.1 (from 2008-03-11) corrects a bug in 2.0 in which some bright (S>500 mJy) sources were missing from the catalogue.