Adenomas and hyperplastic polyps are polypoid lesion and may occur at any location in the colon. At the present moment, all polyps should be resected endoscopically, although only adenomas, but not hyperplastic polyps have the potential to develop colorectal cancer. This approach enables the conduction of microscopic investigations of the lesions. By today, only the pathological diagnosis can distinguish exactly between adenomas and hyperplastic polyps. Some studies have investigated the value of the socalled optical biopsy method. Optical biopsy means the visual assessment of the polyp and the determination of a diagnosis solely on behalf of optical criteria. This method is conducted in real time during colonoscopy. If it can be shown, that endoscopist using optical biopsy are able to predict histopathological diagnoses of colonic polyps sufficiently this would possibly lead to simplification of diagnostic procedures. For instance, it would be conceivable to resect hyperplastic polyps and small adenomas and discard them without further assessment by a pathologist. Gastroenterological societies demand for a 90 percent accordance between diagnoses set by endoscopists and pathologists as a prerequisite for the implementation of the optical biopsy method.