[XXV Anniversary of the Endoscopy-Lithiasis-Laparoscopy (LEL) Working Group].

Introduction: The purpose of this article is to describe the structural vicissitudes and content changes experienced by our Work Group, LEL over the last twenty-five years.

Materials And Methods: The compiled material comes from three sources: the author's experiences; the iconography provided by the co-ordinators; and the data obtained from programmes, letters, etc. This material has been analyzed and organized into six stages and the following has been highlighted in each of these: specific data from each day; key structural data; and the most relevant facts during the period.

Results: Various proposals have been made as a result of the Group's activity: to formally record the endoscopy techniques for the lower urinary tract and extend them to the upper urinary tract: URS and percutaneous surgery, the comprehensive treatment of lithiasis, the defence of our own techniques (such as UTR versus alternatives), as well as to provide an expert opinion on new technologies (laser in urology), and to replace open surgery techniques with others belonging to the Group: PNL and laparoscopy.

Conclusions: For 25 years, the LEL Work Group has stayed active and closely united. It has participated in both internal and external structural changes prompted by the appearance of spectacular new developments that have emerged over this period of time: endoscopic access to the upper urinary tract; comprehensive treatment of lithiasis; and alternatives to traditional surgeries (percutaneous surgery, laparoscopic surgery).