During its "Heart-week" in Feb. 1975, the Danish Heart Foundation drew the attention of the public to the importance of blood pressure measurements as a vital part of health control and prevention. In all, 24 thousand men and women attending supermarkets in Copenhagen took advantage of an offer to have their BP checked. 23% of the screened, who had systolic BP greater than or equal to age+110 (and this sum exceeded 145) and/or diastolic BP greater than or equal to 100 mmHg for all ages, were advised to contact a general practitioner for further evaluation. The campaign showed that it is possible to measure BP and obtain reliable results in an easy, quick, inexpensive and unorthodox way accepted by a public accustomed to free medical care.