As a part of a project performed in general practice 93 recurrent urinary stone formers were examined by means of a programme comprising a thorough medical history, clinical examination, serum determinations, a chemical stone analysis, two consecutive 24h urine collections and i.v.-pyelography. The diagnostic information obtained from the different examinations is presented. In 64 (69%) of the patients the probable aetiology of the stone formation was revealed. Twenty seven (29%) of all patients had combined aetiology. Hyperuricosuria and hypercalciuria were groups of equal size, comprising all together 45 patients, and emphasizing the necessity of 24h urine collections. Hyperparathyroidism (surgically verified) was diagnosed in four patients, based on serum calcium. Seven patients had infectious stone. It is stated that an aetiological examination of the recurrent stone former may be adequately carried out in general practice and lead to important therapeutical consequences.