The along track scanning radiometer (ATSR) is an instrument for the accurate measurement of sea surface temperature, originally developed by the Rutherford Appleton Laboratory (RAL) in the United Kingdom, with substantial design inputs from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia. ATSR-1 was launched on the European ERS-1 satellite in 1991, and has delivered high quality data. Auspace undertook the redesign, fabrication, integration, and test of the infrared focal planes for the follow-on mission, ATSR-2. This was delivered to RAL for integration into the overall instrument, which was successfully launched in April 1995. The Australian role on the follow-on advanced along track scanning radiometer (AATSR) represents about 30% of the overall instrument program, including the redesign, fabrication, integration, and test of both the visible and infrared focal planes for AATSR. The AATSR is scheduled to fly on ESA's ENVISAT program in 1999.