Summary This study explored different mentoring strategies: simulations and case studies regarding ethical dilemmas involved with employment of intellectual developmental disability workers in supported employment using questionnaires of psychological empowerment, self-efficacy, and attitudes toward employing intellectual developmental disability workers in the free market. Participants were 83 social workers and 60 employers and were divided into simulations, case studies, and control groups. All participants in the simulations and case studies groups attended nine mentoring sessions throughout one year, where they completed questionnaires at the beginning, the end, and six months after mentoring. Findings The level of employers’ psychological empowerment and their positive attitudes toward employment of individuals with intellectual developmental disability in their organizations were higher than among the social workers, but the social workers’ self-efficacy level was higher. In addition, we found that mentoring using simulations had more influence than the case studies. The study findings showed that the more dynamic the mentoring, the greater the changes in psychological empowerment perceptions, self-efficacy, and attitudes toward employing intellectual developmental disability workers, both during the study and subsequently. Applications There is considerable importance in developing in-service training and active mentoring for all those involved in the challenges of supported employment. Simulations with participation of actors among social workers and employers, regarding ethical challenges in supported employment are the recommended mentoring methods, as compared to the case studies tested in the current study. Therefore, the study findings encourage the development of advanced mentoring processes among social workers and employers based on simulations, for coping with ethical challenges in supported employment.