In addition to a urinalysis and ultrasound, a computed tomography of the abdomen usually is performed. The number, size and location of the stones can be determined, and thus a tailor-made treatment plan can be developed. After removal, the stones are examined for their exact composition. The knowledge of the stone composition is of great importance to prevent new stone formation. Patients with a high-risk profile will undergo a special metabolic investigation. On the basis of this investigation, we create an individual concept for our stone patients to avoid the formation of new stones.