Health sectors across Europe demand highly qualified nurses. The key to determine the quality of a nurses? performance lies in his/her ability to properly apply domain specific knowledge in various situations. Nursing education is dominated by on-the-job training and learning by doing. To fill existing knowledge gaps, nurses need to participate in (continuous) vocational education and training (e.g. workshops or online courses).Job knowledge includes facts, concepts, principles, and other types of information that enable job holders to perform their tasks properly. The Med-Assess project was targeted at evaluating and assessing the domain knowledge (job knowledge) of nurses, job applicants, and students. The system was realized as a web-based application that employs a multiple-choice test to assess the job knowledge of nurses, and that recommends individually tailored and commensurate learning content for further training and education. The main outcomes of Med-Assess are, therefore, (i) An ontological knowledge-base of nursing job knowledge, (ii) A test bank module (containing multiple choice items), and (iii) A recommender module. The focus was on the selection of employees on the basis of an assessment of their work related knowledge (e.g. the treatment of patients suffering neurological diseases), and the provision of recommendations for remedial training courses, qualification measures, or required learning material. Moreover, Med-Assess supports Vocational Education and Training (VET) on the job and furthers competencies in the context of human health services and the medical profession. The Med-Assess project was specifically focused on, and tailored to, the health labor market in Germany. The ontological approach of Med-Assess is based on the Corvinno developed Studio system. It utilizes ontologies to support a variety of knowledge intensive processes, including learning and assessment. In Med-Assess, Studio reinforces the analysis and assessment of nursing job knowledge. This approach matches nursing requirements and nurses? domain specific knowledge, and provides a logical framework for the assessment of end-users (i.e. job applicants, nurses, and caregivers) by fitting labor market needs to domain specific knowledge.