The Uniform Marriage and Divorce Act (UMDA) was an attempt by the National Conference of Commissioners on Uniform State Laws to make marriage and divorce laws more uniform. This is also known as the Model Marriage and Divorce Act. UMDA was extensively amended in 1973. UMDA is a 1970 model statute that defines marriage and divorce. The greatest significance of UMDA is that it introduced irreconcilable differences as the sole ground for divorce. UMDA has been partly enacted only in a handful of states. However, it has had an enormous impact on marriage and divorce laws in all states.