Full disclosure of medical errors to patients is now widely seen as an essential component of error management, although its update into daily clinical practice is variable. Laboratory diagnostic errors are discovered in retrospective reviews of previous surgical and cytopathology cases. This quality assurance practice is a valuable tool of practice audit and change for both cytotechnologists and pathologists. Presently, these diagnostic errors are only reported to the clinician and patient if the new finding affects current patient management. Mandatory full disclosure of all diagnostic errors discovered in the retrospective review process would have a significant adverse impact on cytotechnologists, pathologists, the laboratory, the clinic, the institution, and insurers. Retrospective pathology review would become so burdensome that its survival would be in jeopardy-unless measures are undertaken to ameliorate the anticipated adverse consequences.