Harrington grew up in Rathfarnham on Dublin's southside. Famous golfers Paul McGinley and Peter Lawrie also came from the suburb, and Harrington attended the same local secondary school (Colaiste Eanna) as McGinley.
The European Tour
The PGA Tour
The Ryder Cup
In 2019, Harrington was named captain of the 2020 European Ryder Cup team. In September 2021, Team Europe suffered a record loss against Team USA, losing 19-9 at Whistling Straits.