The procedures  the Hague Convention

Mediation Process

The Center provides mediation service focusing on amicable resolution for a dispute between a person residing outside of Japan and a person residing in Japan regarding the custody of a child who is younger than 16 (the “International Child Custody Medition Case”).
*Please note that no party needs to pay the application fees and award fee
  if the decision of assistance has been provided by the Japanese Central Authority
  and the budgeted funds remain available.

Application for Mediation Process