During the past years we are witnessing a renaissance of PCNL as primary treatment for renal stones. PCNL is truly on the rise again most probably due to technical refinements of the endoscopic equipment and because of more realism about the efficacy of the SWL therapy.

There are some fundamental (institutional) differences, however, concerning indication for surgery and maybe outcomes. Moreover specific factors may influence treatment related morbidity. In this prospective study we will study on a global base the indications and outcomes of PCNL. Each centre participating in this project will include during a one-year period the patients treated at their site.