Lars Karlsson is a Swedish chess player and International arbiter who was awarded the title of International Master in 1982, followed by the Grandmaster title in 1983. He has been an International Arbiter since 2002. Karlsson was born on January 11, 1955, in Stockholm.
He won the Swedish Chess Championship twice; in 1980 and 1981. He has also participated in eight Chess Olympiads, and was part of the Swedish team that won the gold medal in the European Team Chess Championship in 1980, and the bronze medal in 2005.
In addition to his playing career, Karlsson has contributed to the theoretical development of the game, particularly the Sicilian Defence, Najdorf Variation, and Schveningen Variation. He also participated in organising and hosting major tournaments, such as the Chess Olympiad in 2010.