Working on a limited and controlled population of 100,000 living in the territory of Imola, in northern Italy, we tried to determine the need for coronary arteriography examinations, CABG interventions and PTCA procedures (similarly to the 1980 Minnesota survey). Indications for diagnosis or treatment were made according to agreement criteria of published data in 1990. In the 3 year time (1989-91) of this survey, indication to coronary arteriography was done in 433 pts. (367 atherosclerotic, 58 valvular and 8 with other etiologies). 57.7% (250/433) of the pts. were treated with CABG or PTCA, and 42.3% (202/433) were treated medically. Of the 367 pts. documented as having coronary ischemia, 54.5% had further invasive therapy: 35.4% CABG and 19% PTCA. For a population of 100,000 annual need has been estimated as follows: 145 catheterization procedures (99% coronary arteriography), 60 extracorporeal circulation procedures, and 24 PTCA interventions. Comparing programming estimates done by the national Health System for the needs of a population group in Northern Italy, it is clear that they are underestimating the real needs by 50%, and such an important underestimation implies important and pressing considerations for the future planning of the health care of this important pathology.