In Japan, polygamy is illegal under both civil and criminal law and is considered socially unacceptable due to its association with adultery or cheating on one's spouse. The two main religions practiced in Japan, Shintoism and Buddhism, do not allow for multiple wives or husbands. Additionally, local governments often require couples to obtain a marriage license before they can legally marry; if either partner is already married then they will not be able to obtain a marriage license until their previous marriage has been dissolved through divorce or death of their spouse. Having multiple wives carries an extreme social cost within Japanese society due to its negative connotations associated with infidelity which can lead to ostracism from family members or friends who may disapprove of such practices even if it is done legally elsewhere outside of Japan's jurisdiction.