Japan will introduce its joint custody system on Wednesday, marking a sweeping overhaul of the country¡¯s family law under a revised Civil Code, the first of its kind in over a century.

The change ends Japan¡¯s long-standing sole custody framework, under which only one parent could retain parental rights following a divorce. Under the new system, divorcing couples can choose between joint and sole custody through mutual agreement. Couples who have already divorced may petition family courts to switch from their existing arrangements.

Under joint custody, parents are expected to make major decisions together, including those related to a child¡¯s education or place of residence. Either parent, however, can act independently on routine matters such as meals and clothing, as well as in urgent situations such as medical emergencies.