Below is a link to a 3 part workshop on Special Needs Trusts held at St. Joseph's Hospital in Orange, Ca. The event is being organized by a parent that went through the process of setting up a special needs trust and now runs a conservator support group in Orange County.
In short, special needs trusts are used for beneficiaries who are disabled, either physically or mentally.
I will be attending the Nov. 8th event for my own knowledge