The Uniform Interstate Family Support Act (UIFSA) is a law enacted by all states that provides mechanisms for establishing and enforcing child support obligations in interstate cases. UIFSA defines the issues of jurisdiction over nonresidents and the duties of initiating and responding tribunals. The main concept of UIFSA is once a child support order is entered, that order controls the child support obligation. The order remains in effect whether or not the parents or child later move to another state. UIFSA contains provisions for determining which existing support order will control when multiple orders exist.
In 1996, Congress passed and President Bill Clinton signed the Personal Responsibility and Work Opportunity Act (42 U.S.C. § 666), which required that states adopt UIFSA by January 1, 1998 or face loss of federal funding for child support enforcement. Every U.S. state has adopted either the 1996 or a later version of UIFSA.
The Uniform Law Commission is a good place to go to view previous versions of the Act under Drafting History.