The Uniform Probate Code has shaped state law in this field. It includes provisions dealing with affairs and estates of the deceased and laws dealing with specified nontestamentary transfers, like trusts and their administration. The theory behind the Code is that wills and trusts are in close relationship and thus in need of unification. Since its creation, over thirty percent of states have adopted the Code substantially in whole.
Since many individuals neither set up trusts nor execute wills, state intestate succesion laws are an important complement to trust and estate law. They determine where an individual's assets go upon death in the absence of a will.