 Parr was chairman of Williams Grand Prix Engineering Limited from July 2010 to March 2012, responsible for the day-to-day running of the team, whilst Frank Williams remained Team Principal and majority shareholder of the company.Parr was known during his tenure for his green innovation – bringing hybrid technology to the fore of Williams.In January 2014, he was appointed to the Board of Cosworth, a high performance engineering firm based in Northampton.