EDT: ElastoDynamics Toolbox for MATLAB. The ElastoDynamics Toolbox (EDT) provides an extensive set of MATLAB functions to model wave propagation in layered media. It is based on the direct stiffness method and the thin layer method, presented by Kausel and Roësset. The toolbox is developed at KU Leuven, where it is used both for educational purposes and in research projects. The current version 2.2 (build 20) of the ElastoDynamics Toolbox has been released in August 2010. EDT is used to solve a variety of problems governed by wave propagation in the soil, such as (1) site amplification, (2) the computation of dispersive surface waves in layered soils, and (3) the calculation of the forced response of the soil due to harmonic and transient loading. An example MATLAB M-file that demonstrates the use of EDT can be found here.