A study was carried out on 180 recurrent kidney stone formers from the Campania region of southern Italy. The data showed that this hypercalciuric population was similar to that in previous studies; however, there was no difference in terms of parathyroid activity when compared with normal controls. The slightly depressed serum levels of vitamin D in hypercalciurics indicate that gut calcium absorption is not directly related to vitamin D levels. We found no difference in the prevalence of metabolic abnormalities associated with stone formation between the patients in this series and those in previous studies.