Dr Ewart has a First Class Honours degree from Cambridge and a DPhil from York University. He joined the then Scottish Office in 1977, where his career began in the Education Department. In 1991 he became Deputy Director of the Scottish Courts Administration and guided the Scottish Court Service to agency status, becoming its first Chief Executive in 1994. In 1999 he returned to the Education Department, first as Head of Schools Group, and from 2002, as Head of the Education Department. From April 2007 until November 2009, he was Chief Executive of the Scottish Prison Service.
Dr Ewart is now Director of the Scottish International Education Trust, a non-executive member of the Management Board and Audit and Risk Committee of Education Scotland, a Board member of Phoenix Futures UK and Chair of the Phoenix Scotland Board.
Dr Ewart was appointed in August 2010 for four years. He was reappointed in August 2014 for four years until August 2018.