Rationale, aims and objectives: Resources to deliver healthcare are getting scarce all around the world. Clinical pathways are key tools to make health delivery in clinical settings efficient. C linical pathway design, operation and follow -up all suffer from bad information systems integration. This might badly harm the adherence to clinical pathways. W e have very little research on how clinical pathway s are followed. This stu dy assesses the functioning of a clinical pathway for elderly people in a Finnish case. At the same time it documents the hardships of getting information on the patient flows in a clinical pathway. Method: To support our theoretical discussion with a real case, a case study was performed on the follow- up of clinical pathway for elderly patients in emergency care. The data is on all patients aged 75 years or more who had visited the emergency unit of the city hospital in 2006–2008 was collected. The study sample comprised 24,195 admissions. The flow of patients after the first care at the emergency unit was analyzed, collecting data from various scattered sources. Results: The results show that the planned patient pathways seem not to be followed always. Yearly about 17% of the patients were referred to the university hospital, the more expensive care, but about 74% of these referrals did not follow the agreed procedure. The excess costs of referring patients to a non-standard, more expensive clinical pathway were 2,57 Million Euros over a period of three years for the studied population of 24,195 admissions, also averaging 106 Euros per admission. The case study clearly documents that adherence to the clinical pathway in the case is not as planned, and that system integration difficulties severely harm endeavors to analyze the functioning of and adherence to the pathway. Conclusion: Clinical pathways were not followed in the case as planned and expected. Bad data because of missing system integration made the follow -up of the clinical pathway adherence in our very challenging. Follow-up information of clinical pathway flows is often hard to collect because of fragmented information systems, that are not designed to document patient flows in clinical pathways. Reasons for these conditions should be better understood and studied in more depth.