‘Learning disability’ is a term used in the UK that corresponds to the internationally used ‘mental retardation’. It is determined by low IQ, impaired social adaptation and onset within the developmental period; classification is primarily by IQ. The prevalence of learning disability is rising, mainly due to improved longevity. Several psychiatric disorders are very common among people with learning disability. Promoting the social inclusion of this vulnerable group is one of the greatest challenges to any developed society.