A "Crummey" Trust is simply a trust containing withdrawal rights. The name comes from a taxpayer who used withdrawal rights in an irrevocable trust in the 1960's. The IRS challenged him, and he was forced to go to court. Mr. Crummey won his case--the court held that granting withdrawal rights was a valid estate planning technique. Since that time, Crummey withdrawal rights have become widely used in estate planning.