Confidentiality pertains to the exclusion of information volunteered in mediation sessions from use as evidence in any subsequent legal proceeding. The Florida case of Charles v. Charles (1980) and the Iowa case of Nehrig v. Smith (1951) show courts' intention to encourage mediation by protecting the confidentiality of information derived therefrom. Legislative and judicial decisions regarding mediation confidentiality will largely depend on a balancing test traditionally applied to the claim of privilege. Privilege is granted when the injury caused by the disclosure of communications would exceed the benefit to be derived from the revelation. The strongest argument for the injury of disclosure is the undermining of the public good derived from alternative dispute processing. Some efforts to ensure confidentiality in mediation include agreements between the disputants to abide by the confidentiality principle as well as agreements between mediation programs and local prosecutors that mediation records and other mediation information will not be sought as evidence. Legislation is the best means by protecting confidentiality, since it can eliminate the need to decide the issue in each case. Examples of relevant State laws are discussed. Eighty-six footnotes and a 43-item bibliography are provided. The appendix contains a selected annotation of Federal Rule 26 (on discovery) of the Federal Rules of Civil Procedure.