56 patients with acute myocardial infarction during the period 1973/74, and 58 during the period 1979/80, were questioned immediately after arrival in the coronary care unit about their pre-hospitalization phase. We were able to determine, that the patients' decision time followed by the transportation time accounted for the greater part of the pre-hospitalization period. The contact time between general practitioner and patient played only an insignificant role in the total time-lag. In a comparison of the years 1973/74 and 1979/80 an increase in the patients' decision time and a decrease in the transportation time became evident. Noteworthy was, that in approximately one-fifth of the cases the telephone call to the doctor was not answered. Since an improvement in informing the general public about prodromal symptoms of heart attacks does not seem to bring about a decrease in the decision time, a shortening of the pre-hospitalization period could succeed through a reduction in transportation time and an improvement in doctor accessibility. The use of mobile coronary care units, in particular in rural areas, and improvement in doctors' radio communication services would in that case be matters for discussion.