The Adamson Collection is one of the major international collections of art objects made by people who lived in European mental asylums. It holds about 5,500 objects (paintings, drawings, ceramics, sculptures, and works on stone, flint and bone) created between 1946 and 1981, by people at the British long-stay mental hospital, Netherne.

The Collection is important in the histories of British asylums and post-war psychiatry, of art therapy and Jungians and of outsider art. It was encouraged and collected by an artist Edward Adamson, rather than a psychiatrist, and strongly represents the work of women.

The Adamson Collection Trust (ACT) was founded in 1978 to promote the life and work of Edward Adamson, the future of the Adamson Collection and research into art as therapy. ACT has been maintained by unpaid volunteers – until recently all friends or associates of Edward Adamson.