Collaboration with practicing veterinarians was established in a research project and has resulted in several epidemiologic tools to assist them in their work. Simultaneously, the research group obtained continuous access to valid and precise data and obtained first-hand knowledge about real-life problems for the dairy farmer and the practicing veterinarian. The veterinarian was able to supply detailed information concerning managerial routines applied on the farm. Epidemiologic analyses of the collected data produced input for herd-specific modelling of herd dynamic and economic effects of relevant production alternatives by means of a dynamic, stochastic, and mechanistic simulation model. The relevance of this approach as a research methodology is discussed.