Program Information Founded in 1955, Speech and Language Development Center is a nonprofit school and therapy center that serves students six months through 21 years who have special needs. Our students have a variety of handicapping conditions, including Autism Spectrum Disorder,deaf or hard of hearing, visual impairment, Down Syndrome, seizure disorders, learning handicaps, or emotionally disturbed. Students are referred to the Center by more than 45 school districts and Regional Centers in Orange, Los Angeles, San Bernardino and Riverside counties. SLDC is certified by the California State Department of Education and is licensed by the California State Department of Social Services and Community Care Licensing.