31th OpenMath Workshop (OM21) at CICM 2021 OpenMath is a language for exchanging mathematical formulae across applications (such as computer algebra systems). From 2010 its importance has increased in that OpenMath Content Dictionaries were adopted as a foundation of the MathML 3 W3C recommendation, the standard for mathematical formulae on the Web. The topics of the OpenMath Workshop include • Feature Requests (Standard Enhancement Proposals) and Discussions for going beyond OpenMath 2; • Further convergence of OpenMath and MathML 3; • Reasoning with OpenMath; • OpenMath on the Semantic Web; • New OpenMath Content Dictionaries; • Software using or processing OpenMath The 31. OpenMath Workshop included three talks of which two were contributed to this volume. James H. Davenport & Michael Kohlhase CICM 2021: 14th Conference on Intelligent Computer Mathematics, July 26–31, 2021, Timisoara, Romania © 2022 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0). CEUR Workshop Proceedings http://ceur-ws.org ISSN 1613-0073 CEUR Workshop Proceedings (CEUR-WS.org)