This is a retrospective study of 142 stone-formers admitted during 1981 to a general surgical unit of a district hospital. The majority were adult non-Kuwaiti males. Contrary to expectations it was the manual workers from lower economical social strata who were commonly afflicted. The possible reasons for this are discussed. There were no specific biochemical defects in the patients' sera but of 22 patients whose 24-hour urines were examined, half had some abnormality. The majority of IVPs showed some anatomical abnormalities. Calculi were passed spontaneously in nearly half of the patients.