Communications in Combinatorics and Optimization (CCO) is a peer-reviewed journal published quarterly. The journal is devoted to advancing and promoting both the theory and applications of combinatorics and optimization, including interdisciplinary research. CCO aims to publish original, high-quality, refereed papers, as well as occasional survey articles and short notes. There are no fees for submission, processing, or publication in Communications in Combinatorics and Optimization. Since 2023, four issues have been published each year, appearing at the end of March, June, September, and December.