Polygamy (a practice that overlaps heavily with polyamory) is the practice of legally marrying more than one person. It is against the law to marry more than one person in the United States; however, there are many countries around the world where polygamy and/or polyamorous relationships are not unusual. For example, it is not uncommon in many middle eastern cultures for men to have multiple wives. This type of polyamorous relationship is known as polygyny.