Peter Heine Nielsen (born May 24, 1973) is a Danish chess player, coach, and commentator.
Nielsen coached World Champion Vishy Anand from 2002 until 2012. Anand won the World Championship title in Mexico 2007, and defended it in Bonn 2008, Sofia 2010 and Moscow 2012.
Nielsen has been coaching world number one, Magnus Carlsen, since 2013. In 2013 Carlsen won the Candidates tournament giving him the right to challenge Vishy Anand for his title, which he later did and won.
Nielsen coached Carlsen in Khanty-Mansiysk 2005, when Carlsen as the youngest ever qualified for the candidate matches. More: en.wikipedia.org.