BACKGROUND: Development of clinical practice at a Danish neurorehabilitation centre was delegated to a group of health professional developers. Their job function lacked conceptual foundation, and it was unclear how their working tasks contributed to evidence-based practice. OBJECTIVE: Conceptual clarification of the job function and pattern analysis of activity distributions for health professional developers. METHODS: Health professional developers kept continuous time geographical diaries for two weeks. Meaningful categories were subtracted through content analysis. Patterns were analysed within activity distributions with regards to evidence-based practice. RESULTS: A total of 213 diaries were collected from 21 health professional developers of three professions (physiotherapists, occupational therapists and nurses). Each participant reported 6-13 workdays (median 10 days). Eleven main categories of work tasks emerged with 42 subcategories. Overall, 7% of total time reported was spent on external knowledge, with minimal variation between professions and contractual time allocation. CONCLUSION: Conceptual clarification of work tasks was established for health professional developers. Their work activity distributions contributed mainly to maintenance of existing level of professional knowledge rather than to implementation of new knowledge, which did not fulfil the intended responsibility for development of evidence-based practice. Educational competence boost and data-driven change of organisation structure was recommended.