It is essential to identify patients with premalignant or early malignant changes during colonoscopy. Thus, curative resection can be offered. At present, endoscopy can be performed with new powerful high-resolution or magnifying endoscopes. Comparably to the rapid development in chip technology, the optic features of the newly designed endoscopes offer resolutions which allow new mucosal surface details to be seen. In conjunction with chromoendoscopy, the newly discovered tool video endoscopy is much easier and more impressive than with conventional fibre optics. This review summarizes the value of magnifying endoscopy in the lower gastrointestinal tract and focuses on colorectal lesions.