Colonoscopy is the recommended method for diagnosis of colorectal diseases but the number of neoplastic lesions missed is not negligible. To reduce this it is necessary to achieve quality standards in colonoscopy, for example the extent of cecal intubation, adequate bowel cleansing, and appropriate withdrawal time. Conventional wisdom is that proper colonoscopy training is the most important aspect of detection of subtle lesions. Systematic examination, including careful inspection behind folds, removal of residual stools by lavage, and awareness of and an active search for subtle mucosal abnormalities, are key factors in increasing detection of neoplastic lesions. In addition, ancillary techniques might aid detection or better characterization of additional lesions. This review focuses on the requirements for a high quality colonoscopy and on the novel techniques that may improve detection of adenoma.