A lay organisation is created to pursue a common goal by non-experts ( lay men) in the field of interest. This is often because there isn't a professional body which fulfills the common objectives of a group of people. They are commonly formed as a more structured self-help group by sufferers and carers for conditions and illnesses not yet fully supported by the medical establishment. They are often continued in addition to official medical bodies since their collective experience provides valuable support for others seeking help.
'Lay' is derived from Anglo-French Lai, meaning 'of the people' or 'the people at large'. In religous terms the laity refers to all persons who are not clergy. The early lay organisations were religous based, e.g. the Women's Missionary Society (WMS) (1864 to 1989). In the late 1800s, the Montreal Woman's Missionary Society secured the services of Mine Cote. For 30 years, she visited and provided care and support for the poor in Montreal, Canada.
The earliest modern lay organisation is considered to be Alcoholics Anonymous which was formed in the 1930s by Bill Wilson, after seeking several avenues to cure his alcoholism and being influenced by Ebby Thacher a member of a Christian movement called the Oxford Group, Dr. William Silkworth, a proponent of the disease concept of alcoholism, and collaboration with another alcoholic Dr. Bob Smith. Using his own methods Smith's last drink was on June 10, 1935 is considered to be the founding date after which Wilson and Smith co-founded AA with a word of mouth program to help other alcoholics. 
- Borgetto B, von dem Knesebeck O (2009). "[Patient self-help, user perspective and health services research]". Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz (in German) 52 (1): 21–9. doi:10.1007/s00103-009-0744-5. PMID 19189151. Retrieved 2009-08-01. Unknown parameter
- Pass It on: The Story of Bill Wilson and how the A.A. Message Reached the World. New York, NY: Alcoholics Anonymous World Services, Inc. December 1984. pp. 131–149. ISBN 9780916856120.