five million intellectual and developmental disabilities http://www.thearc.org/page.aspx?pid=2448 living with I/DD The ARC: introducción a las discapacidades intelectuales http://www.thearc.org/page.aspx?pid=2448 intellectual and developmental disabilities intellectual and developmental disabilities The Arc: introducción para discapacidades intelectuales living with I/DD Intellectual/Developmental Disabilities (I/DD) Fact Sheet living with I/DD The Arc - National intellectual and developmental disabilities Introduction to Intellectual Disabilities living with I/DD