Tools to assess problem-solving skills are limited, and comprehensive evaluation is difficult. Concept mapping might be used to evaluate learners' organization of knowledge at various points during training. We used concept mapping to evaluate postgraduate training at the Department of Education Training Technology and Development, National Institute of Public Health. Thirty-five healthcare workers, including physicians, and public health nurses, underwent concept mapping training, drew preinstruction concept maps about public health or community organization, completed an educational course, and then drew postinstruction concept maps. Maps were assessed independently through qualitative comparison of concepts, conceptual links, hierarchy, knowledge domains, cross-links, and examples of preinstruction and postinstitution maps. This study provides preliminary evidence that concept mapping reflects changes and differences in the conceptual framework of individuals and of members of different healthcare specialties. Concept mapping can be used to clarify conceptual frameworks and to develop problem-solving skills. Moreover, concept mapping might be used to evaluate problem-solving skills.