Published online by Cambridge University Press: 03 August 2017
QUASAT was proposed to ESA as a joint ESA-NASA medium scale mission for space VLBI in December 1982. At the time of writing, four and a half years later, QUASAT has passed through an Assessment Study in ESA, a pre-Phase A study in NASA and has just entered an ESA Phase A study in European industry, supported by JPL and Australian and Canadian space interests. If QUASAT is selected to fly at the end of the Phase A study, it will be launched in 1995–1996. The scientific goals, mission concept and current status are reviewed this paper.