Annals of Coloproctology (ACP) allows authors to submit preprints to the journal. A preprint can be defined as a version of a scholarly paper that precedes formal peer review and publication in a peer-reviewed scholarly journal. It is not treated as duplicate submission or duplicate publication. ACP recommends that authors disclose the existence of the preprint with its DOI in the letter to the Editor during the submission process. Otherwise, a plagiarism check program (Similarity Check), may flag the results as containing excessive duplication. A preprint submission will be processed through the same peer-review process as a usual submission. If a preprint is accepted for publication, the authors are recommended to update the information on the preprint site with a link to the published article in ACP, including the DOI at ACP. It is strongly recommended that authors cite the article in ACP instead of the preprint in their next submission to journals.