On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue its role in research, the following key messages were retained. The growing number of publications, dissertations, theses and teams involved shows that the REIN registry has attained its objective of being a shared research infrastructure, in the field of epidemiology as well as in public health, health economics or medical data processing. REIN is a valuable tool for the study of specific kidney diseases, particularly for epidemiological data pertaining to rare diseases that may lead to stage 5 of a chronic kidney disease. The linkage with the data from the National Healthcare Data System enables integrating and analysing the medical treatments received by patients, before the initiation of the replacement therapy and towards the end, as well as the details of the hospital stays.