Orientation: Mediation is becoming an increasingly popular conciliatory procedure, which makes it possible to increase the psychological protection of parties in disputes in educational, social environment and legal practice.Research purpose: To develop and empirically confirm the model of mediators’ professional competencies to determine the features of mediators’ professional competencies and personal characteristics in the conciliation procedure with varying degrees of success.Motivation for the study: Today, the profession of mediator is becoming increasingly popular; however, there is not enough information in scientific literature about the issues of specialists’ professional suitability to training and experience, desirable personality traits and competencies.Research approach/ design and method: A total of 103 mediators from the Russian Arkhangelsk region took part in the study. Research methods include psychological testing using Bardin and Presnov’s ‘11 personality factors’, Costa and McCray’s Five-Factor Personality Questionnaire adapted by Bodunov and Biryukov and questioning (the author’s self-assessment questionnaire of mediators’ professional competencies). Statistical processing was carried out using descriptive statistics, correlation (Pearson’s χ2), multivariate variance and stepwise multiple regression analysis using the SPSS 23 software package.Main findings: The mediators’ professional competence model includes communication, conflict management, problem analysis, planning and self-control. A self-assessment questionnaire for mediators’ professional competencies, which can be used by the 360-degree method, has been developed and tested. A conclusion was made that the success of a conciliation procedure is influenced by such personal qualities as self-control, communication, curiosity and morality. From the list of mediators’ professional qualities, compiled by the authors, the following ones directly influence the success of mediation: activity, specificity, openness, poise, organisation, responsibility and communication skills.Practical/managerial implications: It is necessary to provide additional support for novice mediators, because this will facilitate more active involvement in activities, conduct more conciliation process and subsequently lead to increased success.Contribution/value-add: The developed questionnaire for assessing professional competencies will help in the training and selection of mediators. It will allow us to highlight what key and specific competencies of the mediator hinder the achievement of a successful result in the rehabilitation procedure and require development.