The 3D Dynamics module is an extension to PLAXIS 3D. Geotechnical applications require advanced constitutive models for the simulation of the non linear, time dependent and anisotropic behaviour of soils and/or rock. Although the modelling of the soil itself is an important issue, many projects involve the modelling of structures and the interaction between the structures and the soil. The Dynamics module offers the tools to analyse the propagation of waves through the soil and their influence on structures. This allows for the analysis of seismic loading as well as vibrations due to construction activities. PLAXIS Dynamics offers the possibility to perform dynamic calculations in individual calculation phases.