Clinical aspects of stone formation and conservative treatment need to consider the following factors: (1) Epidemiological studies and their knowledge are necessary as they have permitted important conclusions with the regard to risk and history of urolithiasis. (2) Laboratory diagnosis is a prerequisite to therapy. Mode and extent of laboratory investigations depend whether or not proven measures can result. The distinction between practice and research and their demands must clearly be made. (3) Risk-orientated laboratory parameters must be assessed from a point of view which concentrates on the possibility of therapeutic influence. Looking for and finding abnormal values is more likely to satisfy the statistician than the clinician. (4) The choice of treatment depends not only on laboratory values but also on the individual characteristics of the patient such as sex, age, occupation and education as well as general state of health and its impairment by stone recurrence. (5) Classic (diuresis and diet) as well as drug therapy need clear indications, where risk and benefit must be balanced individually. Therapy needs to be controlled on the one hand in order to make indications safer through increasing experience, and on the other hand to make indications preciser by the analysis of failures.