PRISMS (Parents and Researchers Interested in Smith-Magenis Syndrome) - Details about the international support group organization and its mission as well as the condition. Includes an introduction, diagnosis, parent's corner, meet other people with SMS and educational considerations. - http://www.prisms.org
NORD: Smith Magenis Syndrome - Offers the synonyms, a general discussion and further resources. - http://www.rarediseases.org/search/rdbdetail_abstract.html?disname=Smith%20Lemli%20Opitz%20Syndrome
The CaF Directory - A definition of Smith-Magenis syndrome, its inheritance pattern, pre-natal diagnosis and a support group in the United Kingdom. - http://www.cafamily.org.uk/Direct/s33.html