after retiring from active driving, harrington has achieved success in his driver coaching business, including coaching highcroft racing factory acura team championship winning owner-driver duncan dayton and mike miserandino who has won four national championships in a row. in 2017 two of his customers won again at the runoffs, mike miserandino won his fifth national title with scott's coaching and young max gee won his first with scott on board, coaching him to his first national championship. his latest driver, jacob abel won two of the three f3 americas races at the road atlanta round. he also competes in a number of vintage endurance races every year. in 2014 his vintage coaching customer bill abel won a national championship at the svra national championship at the circuit of the americas. in addition to his testing and training work, harrington does promotional and testing work for various manufacturers.