California Code, Welfare and Institutions Code - WIC § 4640

(a) Contracts between the department and regional centers shall specify the service area and the categories of persons that regional centers shall be expected to serve and the services and supports to be provided.

(b) In order to ensure uniformity in the application of the definition of developmental disability contained in this division, the Director of Developmental Services shall, by March 1, 1977, issue regulations that delineate, by diagnostic category and degree of disability, those persons who are eligible for services and supports by regional centers. In issuing the regulations, the director shall invite and consider the views of regional center contracting agencies, the state council, and persons with a demonstrated and direct interest in developmental disabilities.