Since the beginning of modern day endodontics, there have been numerous concepts, strategies, and techniques for preparing canals. Throughout decades, a staggering array of files has emerged for negotiating and shaping canals. In spite of the design of the file, the number of instruments required, and the surprising multitude of techniques advocated, endodontic treatment has been typically approached with optimism for probable success. The common misconception today is that dentists tend to relate to all root canals as if they had a uniform round cross section. This is true for the upper incisors, but wrong for every other tooth in maxilla and mandible. The Self-adjusting file (SAF) brings a new concept to the table in terms of root canal treatment. First of all, it is a system that combines irrigation and instrumentation at the same time. The special design of the instrument allows its compression inside the canals and three dimensional adjustment, no matter how complicated the configuration of root canal is, without fear of breakage. In addition, this instrument has the ability of circumferential removal of dentin to give better adhesion of the future filling and the canal wall. Surface of the SAF has a roughness of 2.8 μm ± 10 % which gives a file scraping feature and a possibility to smoothen walls of the root canal. It generates a vibration of 5000 rpm. With the SAF, goals like minimal reduction and uniformity of the remaining wall thickness become achievable. The prevention of canal transportation, continuous irrigation with sodium hypochlorite and high durability are just a few specifications that make this system a step towards a whole new era in modern endodontics.