In the past decade the amount of legislation and litigation involving informal marriages has increased. Historically, a close connection between marriage and property law has existed. However, children today are less important for property inheritance purposes because informal marriages have increased in popularity and are accepted among diverse social groups. The Family Law Act in Australia permits divorce on grounds of irretrievable breakdown and also prescribes the rights and obligations of marriage partners. Any relationship outside of marriage, however, must be legislated at the state level. In Australia the legal reaction to informal marriages has been sporadic, inconsistent and contradictory, although a body of case and statute law covers aspects of unmarried cohabitation. This trend is also evident in countries with similar legal systems. (RC)