In 1999 Houstoun received an honorary doctorate in literature from Massey University. Houstoun started suffering from focal hand dystonia, which could easily have ended his career. The condition was treated with physiotherapy and acupuncture, and he had splints made, used rubber bands, and learned braille as sensory retraining, but Houstoun believes that his relaxation technique helped him overcome the condition. In 2001 a documentary was filmed about his condition. After five years he started performing again as a soloist. In the 2012 Queen's Birthday and Diamond Jubilee Honours Houstoun was appointed a Companion of the New Zealand Order of Merit for services as a pianist.