Confidentiality in mediation proceedings is intended to prevent the parties from using facts revealed in mediation in subsequent legal proceedings. The Federal rules of evidence give some mediation confidentiality protection. Rule 408 renders inadmissible evidence consisting of statements made during settlement negotiations to prove 'liability for, invalidity of, or the amount of the claim or any other claim.' Proposed Massachusetts Rule of Evidence 408 is identical to the Federal rule in this regard. Also, the parole evidence rule would exclude oral evidence to vary the terms of a mediated agreement. The Boston Municipal Court Mediation Program also provides for the parties and the mediator signing a nondisclosure agreement. The attorney-mediator is not bound by the principle of attorney-client privilege in mediation communications since the parties are nonclients, but an exception to the attorney-client privilege principle does apply to the attorney-mediator. Any evidence regarding a party's commission of a crime must be revealed. Forty-seven footnotes are listed.