This study seeks to establish the relative importance of service access and quality on utilization of preventive health services in the western and middle-western Hill region of Nepal. Access was measured in terms of travel time to the nearest health post and coverage by outreach workers. The quality of static services was defined in structural terms: physical infrastructure, number of staff, availability of drugs and holding of special maternal and child health clinics. The initial analysis showed that no single indicator of quality was of overriding importance and therefore an overall quality index was constructed. After adjustment for access and for socioeconomic characteristics of families and communities, a very pronounced relationship between overall structural quality of the nearest health post and service uptake persisted. The adjusted odds of using some form of antenatal service were 6.6 times higher in the catchment areas of high quality posts than in areas served by low quality posts. The corresponding figure for receipt of BCG vaccination is 8.1. By comparison, the effects of travel time to the nearest health post are modest. Uptake of services is about twice as high when there is a health post in the community. Regular monthly visits by outreach workers also had a marked effect on service utilization. These results suggest that investment in the quality of health posts is more important than further increases in their number and that a further expansion of outreach services is a priority.