Hospital discharge summary data were used to identify and study all 2,870 Rhode Island residents hospitalized in-state with head injuries during 1979 and 1980. The overall hospitalized incidence rate was 152 per 100,000 of population per year with age and sex variations similar to those found in other studies. This is consistent with the observation that fatal injury rates in Rhode Island are only 75 per cent of the United States average. Hospitalized incidence rates of head injury for the census tracts in the lowest decile of median income were twice those for census tracts in the highest decile. Smaller increases were also observed with increasing population density. Length of hospital stay increased with age. Discharge to chronic care facilities plus in-hospital deaths increased 20-fold with increasing age. In each age group, in-hospital deaths and discharge to chronic care facilities were associated with long hospital stays.