In many jurisdictions, mediation is a voluntary process. Therefore, the parties may not refer to or be forced to refer to mediation unless both of the parties wish so. The parties may mutually decide upon referring to mediation after a dispute has arisen between them, even while the court proceedings are pending; or they may enact a mediation agreement for a potential dispute that might arise, in the future, in connection with an existing legal relation between them. In practice, usually a prior mediation agreement exists as a part of a main contract between the parties, in order to enable those parties to resort to mediation in case of a dispute that might arise out of that contract. However, despite a prior written mediation agreement, the parties may always refer to courts. There is no legal consequence of referring to the court before trying mediation despite the existence of a mediation agreement. In other words, a prior mediation agreement is not binding upon the parties; there is no legal way to force an unwilling party to refer to or continue mediation. It is not possible for the parties to refer to mediation for all kinds of disputes. According to Article 1/2 of the Mediation Law, only private law disputes arising out of matters that the parties may freely dispose of, including those that carry a foreign element, can be subject to mediation. Therefore, the disputes arising out of subject matters related with public policy can not be referred to mediation. For example, spouses may not refer to mediation for divorce; or disputes concerning affiliation of a child to one of his/her parents may not be subject to mediation. Therefore, the correct option is D.