As computed tomographic (CT) colonography is being used increasingly in clinical practice, an effective quality improvement process must be ensured. The quality improvement process is outlined for the reader by using an adverse event during CT colonography as an example. Components of this process are the approach to a sentinel event, performance of a root cause analysis, and development of strategies for minimizing errors after a serious adverse event. Important factors include indications and contraindications for the examination, proper imaging technique, training of personnel, complications of the procedure, and legal implications. Complications from CT colonography are rare. Attention must be paid to the correct technique for colonic insufflation, particularly in older patients and those who are symptomatic. Root cause analysis provides valuable tools for identification and implementation of improvements designed to avoid similar and other adverse events and to minimize damage.