OBJECTIVES: To evaluate the use of ambulatory blood pressure monitoring in comparison with home and office blood pressure in every-day general practice. METHODS: In a multicenter survey sixty-two practitioners previously unfamiliar with ambulatory blood pressure monitoring performed a total of 1162 (mean 18 +/- 16; range 3-94) 24-h ambulatory- and home blood pressure measurements in normotensive subjects or patients with untreated or treated hypertension. RESULTS: In subjects with office blood pressure or = 140/90 mmHg had 24-h ambulatory blood pressure averaging 141/88 mmHg, home blood pressure 149/93 mmHg, and office blood pressure 157/95 mmHg. The difference between office-, home-, and ambulatory blood pressure increased with age. Expected differences were found between the three blood pressure modalities according to indication of examination (borderline -, "white-coat" -, and therapy refractory hypertension). Indices of hypertension related end-organ damage were positively correlated with home and ambulatory blood pressure but not with office blood pressure. Overall the performance of home- and ambulatory blood pressure in this general practice setting was similar to that seen by specialized blood pressure units. CONCLUSION: This study demonstrates the practical utility of home- and ambulatory blood pressure measurement in every-day general practice. Both methods are easy to introduce and the quality of blood pressure data obtained in every-day general practice are comparable to those obtained in hypertension clinics and trial centers.