In the literature section of the present dissertation a detailed account is given of the growing importance of health promotion and burnout prevention for teachers. Apart from outlining the theoretical basics of mental health problems, the aim of this study was to develop, carry out, and evaluate a prevention program for teachers called (GO!-L). This program contains primary preventive measures against stress, anxiety, depression and burnout. GO!-L can be regarded as an upward revision of the youth version GO! (Junge, Neumer, Manz & Margraf 2002) which is successfully applied in schools and has proven to be efficient in several studies. In the present study GO-L was evaluated in a quasi-experimental design, including both a training and control group (N= 48 teachers). Specific program-related variables were assessed at four measurement occasions, including a three-month follow-up. High-quality interviews and a formative evaluation completed the design. The training group showed a significant increase of knowledge concerning mental health problems. Furthermore, a decrease in depression and anxiety scores as well as in perceived occupational workload could be detected in the training group. Self-efficacy turned out to be a relatively stable trait. Work-related behavior and experience patterns of the participants changed in the direction of health-promotion - an increase of Type B (easy-going) individuals and decrease of Type A (high-strung) individuals was found. Altogether the results of the present study speak for the program?s efficacy. Participants considered GO!-L to be an excellent program and assessed content, methodology, competence of trainers, and structure as very good. Already in the pilot-phase GO!-L proves to be suitable for daily use and adequate for the target group of teachers. So an even better outcome can be expected in empirical studies with larger samples and by making the program part of encompassing health promotion measures.