The Clinical Research Office of the Endourological Society (CROES) initiated the facilitation of a worldwide cooperation between endourologists. The CROES is responsible for six registries: PCNL, URS, GLS, Renal Mass, UTUC and IRE. The CROES also started three RCT’s: NBI, S‑Technologies and IRE. The S‑Technologies- and IRE-RCT, and UTUC- and IRE-registry are now open for inclusion! In order to facilitate the collection of data for CROES related studies a new data management system (DMS) was developed. Entered data should be reliable and valid. This goal is accomplished by using a data transfer agreement for centers before they can start participating in a study, monitoring the data, and assigning an audit committee to assure validation. Centers can always retrieve and publish their own data.