OBJECTIVES: To explore whether implementation of free high-quality care as part of research programmes resulted in greater health facility attendance by sick children. METHODS: As part of the Intermittent Preventive Treatment for Malaria in Infants (IPTi), begun in 2004, and population-based infectious disease surveillance (PBIDS), begun in 2005 in Asembo, rural western Kenya, free high-quality care was offered to infants and persons of all ages, respectively, at one Asembo facility, Lwak Hospital. We compared rates of sick-child visits by children <10 years to all seven Asembo clinics before and after implementation of free high-quality care in 10 intervention villages closest to Lwak Hospital and 8 nearby comparison villages not participating in the studies. Incidence rates and rate ratios for sick-child visits were compared between intervention and comparison villages by time period using Poisson regression. RESULTS: After IPTi began, the rate of sick-child visits for infants, the study's target group, in intervention villages increased by 191% (95% CI 75-384) more than in comparison villages, but did not increase significantly more in older children. After PBIDS began, the rate of sick-child visits in intervention villages increased by 267% (95% CI 76-661) more than that in comparison villages for all children <10 years. The greatest increases in visit rates in intervention villages occurred 3-6 months after the intervention started. Visits for cough showed greater increases than visits for fever or diarrhoea. CONCLUSIONS: Implementation of free high-quality care increased healthcare use by sick children. Cost and quality of care are potentially modifiable barriers to improving access to care in rural Africa.