The aim of the project this paper is part of was to propose quality and safety procedures and indicators to facilitate quality improvement in digestive endoscopy units. In this second issue, procedures and indicators are suggested regarding colonoscopy. First, a diagram charting the previous and subsequent steps of colonoscopy was designed. A group of experts in health care quality and/or endoscopy, under the auspices of the Sociedad Española de Patología Digestiva (SEPD), performed a qualitative review of the literature regarding colonoscopy-related quality indicators. Subsequently, using a paired-analysis method, the aforementioned literature was selected and analyzed. A total of 13 specific indicators were found aside of the common markers elsewhere described, ten of which are process-related (one pre-procedure, seven procedure, and two post-procedure markers) while the remaining three are outcome-related. Quality of evidence was assessed for each one of them using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) classification.