This chapter explains how to use the moving mesh functionality for adding moving meshes to COMSOL Multiphysics models. There is also information about the dedicated interfaces that control mesh deformation, which you find under the Mathematics>Deformed Mesh branch () when adding physics interfaces to a model. It also contains fundamentals about deformed meshes and information about the Eulerian and Lagrangian formulations of the physics, the frame types that support these formulations, and the arbitrary Lagrangian-Eulerian (ALE) method.