In a multicenter, national, open study were evaluated effectiveness and safety profile of Eprosartan (ES), in monotherapy or in combination with diuretics (D). 1954 mild-to-moderate essential hypertensive patients were followed during 1 year, at Primary Care setting. 412 (21,1%) patients were excluded due to protocol violations. 1542 (828 – 53,7 % females) patients had a mean age 63 ± 11.5 years, mean BMI: 28,2 ±4 Kg/m2, and mean BP 163,3 ± 11 / 95 ± 7,7 mmHg having 23,2 % mild and 62 % moderate essential hypertension, while 14,8 % had ISH. At baseline, 6 weeks, 5, 9 and 12 months, were measured BP (2 readings), HR, BMI and side-effects, and determined fasten levels of glucose, K+, uric acid, creatinine and lipids. After a wash-out period, all patients received ES 600 mg once/day. After a 6-weeks period, a low-dose diuretic was added (HCTZ 12.5 mg or torasemide 2.5 mg), if BP≥ 140/90. 6 weeks later, uncontrolled pts received doubled dose of diuretic. Pts that remained uncontrolled after 3 months, Beta/Alphablocker or CCB were added to reach BP control. Mean BP decreased from 163,3±11 / 95±8 to 136.6±9 79.7 ± 6 mmHg (p<0.001) without statistical changes in HR, BMI and biochemical parameters.82 (5,32%) showed side-effects and 146 (9,47 %) pts withdrew the study. From the remaning 1396 pts, 88.11 % (n-1230) were controlled (BP < 140/90) at 12 months, either in monotherapy ( 726 / 52 %) or in combination with diuretics (504 / 36,14%), needing 155 (11.10 %) of them the addition of others drugs. Long-term eprosartan therapy, with or without diuretics, showed a high antihypertensive effectiveness and was well tolerated in the treatment of mild-to-moderate essential hypertension.