A sodium intervention project was carried out in Tianjin, China, as part of the Tianjin Project, which is a national pilot, community-based intervention programme to reduce non-communicable diseases. The aim of this 3 year sodium project was to evaluate the feasibility and effects of sodium reduction in the population. The evaluation of the programme was based on examinations of independent cross-sectional population samples in 1989 (1719 persons) and in 1992 (2304 persons) in the intervention and matched reference areas. Food weighing and consecutive 3 day food records were used to measure dietary intake. The mean sodium intake fell 22 mmol/day in men and 11 mmol/day in women in the intervention area from 1989 to 1992. The reduction was significant in men (P = 0.001) and near significance in women (P = 0.05). The sodium intake increased significantly in men in the reference area. There was a significant net reduction in sodium intake in men in the intervention area. This reduction was similar in different educational and occupational groups suggesting that the intervention had reached the whole community. The mean systolic blood pressure (SBP) decreased 3 mm Hg for the total population and 2 mm Hg for normotensives in the intervention area. There was a significant net reduction in SBP both in all or in normotensive subjects. These results support the conclusion that community-based sodium intervention is feasible for hypertension prevention. However, the sodium intake is still very high in this population, which warrants further effective intervention.