Welcome to the 4th Workshop on Computational Approaches to Discourse, CODI! CODI provides a venue to bring together researchers working on all aspects of discourse in Computational Linguistics and NLP. Our aim is to provide a venue for the entire discourse processing community where we can present and exchange our theories, algorithms, software, datasets, and tools. The workshop consists of invited talks, contributed papers, extended abstracts, and ACL Findings presentations. We received paper submissions that span a wide range of topics, addressing issues related to discourse representation and parsing, reference and coreference resolution, summarization, dialogue, pragmatics, applications, and more. As the workshop is hybrid this year, papers are presented live either in person or remotely and discussed during live Q&A sessions. We are pleased that CODI 2023 features the third edition of the DISRPT (DIScourse Relation Parsing and Treebanking) shared task on Discourse Segmentation, Connective and Relation Identification across Formalisms. As we hope that the next CODI workshops will also feature shared tasks and other special events, the workshop also includes a discussion on future shared tasks, special sessions on discourse representation and parsing, coreference resolution, and multilingual discourse processing and machine translation. We thank our invited speakers, Yufang Hou, IBM Research Ireland and adjunct senior lecturer and co-supervisor at UKP Lab-TU Darmstadt, who works on referential discourse modeling, argument mining, and scholarly document processing; and Giuseppe Carenini, University of British Columbia, known for his work on discourse parsing, summarization, and generation. We would also like to thank our reviewers for their thoughtful and instructive comments. They helped us to prepare an excellent and inclusive workshop program. Finally we would like to thank the ACL 2023 workshop chairs Eduardo Blanco, Yang Feng, and Annie Louis who organized the ACL workshops program.