A study on the global trend of accreditation for mediators implies many important aspects of controlling of the quality of mediation. Firstly, whether or not having an accreditation system, most European countries and the U.S. have a common understanding on the fact that mediators need to be trained to mediate disputes, apart from their own expertise on the subject matters. Secondly, private-led accreditation has been utilized in countries having a Anglo-American law system such as the United Kingdom and the U.S. a while nation-managed one has been operated in the countries having a continental law system such as Austria, Belgium, Italy and Germany. Thirdly, private mediation service providers (usually institutions or companies) play an active role in the training and accreditation of mediators and further make them act as mediators in the disputes referred to them. Fourthly, the countries having a nation-managed accreditation system usually stipulate a certain mediation training and accreditation requirement by law. Fifthly, there is no uniform trend on the minimum hours of training required for accrediting the mediators. Sixthly, mediation training generally focuses on the practical mediation capacity-building, including mediation theory and role-playing, mediation simulations, peer review and supervision. And finally, the mediation theory mainly includes the role of mediator, mediation procedures, mediation communication, negotiation and communication skills, mediation ethics and mediator's code of conduct, etc.