Lieutenant Colonel Herbert George "Blondie" Hasler, DSO, OBE (27 February 1914 – 5 May 1987) was a distinguished Royal Marines officer in the Second World War. In December 1942 he led a small commando raid against Axis shipping in Bordeaux. He was responsible for many of the concepts which ultimately led to the post-war formation of the Special Boat Service. After the war he became a notable yachtsman, contributing especially to developments in single-handed sailing.