On 1 March 2003 the default urban speed limit in South Australia was reduced from 60 km/h to 50 km/h. The Centre for Automotive Safety Research was commissioned by the Department of Transport and Urban Planning (DTUP) to conduct an evaluation of the new 50 km/h default urban speed limit in terms of changes in vehicle travelling speeds and casualty crash numbers. On-road speeds just before the default limit was introduced were compared with speeds a year later.
