  This volume contains the papers presented at the 18th International Overture
Workshop, held online on 7th December 2020. This event was the latest in a
series of workshops around the Vienna Development Method (VDM), the open-source
project Overture, and related tools and formalisms. VDM is one of the longest
established formal methods for systems development. A lively community of
researchers and practitioners has grown up in academia and industry has grown
around the modelling languages (VDM-SL, VDM++, VDM-RT, CML) and tools
(VDMTools, Overture, Crescendo, Symphony, the INTO-CPS chain, and ViennaTalk).
Together, these provide a platform for work on modelling and analysis
technology that includes static and dynamic analysis, test generation,
execution support, and model checking. This workshop provided updates on the
emerging technology of VDM/Overture, including collaboration infrastructure,
collaborative modelling and co-simulation for Cyber-Physical Systems.
