In a study on the long-term outcome after thrombolysis in patients with acute myocardial infarction, we had to ascertain the cause of death as noted in the confidential section of the official death certificate at the Public Health Office. Since current data protection legislation does not permit direct access to the death certificates we used a custodian model which strictly separates the institution storing the addresses in touch, and carries out the inquiry and the institution receiving the anonymised data for analysis. Forty Public Health Offices in ten German Bundesländer were asked for causes of death of 118 patients. Data were delivered by 35 Public Health Offices from nine Bundesländer on 106 patients (response = 89.8%). The custodian model which was often proposed as a tool for epidemiological research within the restrictive legal framework in Germany, proved to be successful in practice, with good response.