DAE Tools is cross-platform equation-oriented process modelling, simulation, and optimization software. Various types of processes (lumped or distributed, steady-state or dynamic) can be modelled and optimized. They may range from very simple to those which require complex operating procedures. Equations can be ordinary or discontinuous, where discontinuities are automatically handled by the framework. Model reports containing all information about a model can be exported in XML MathML format, automatically creating high-quality documentation. The simulation results can be visualized, plotted, and/or exported into various formats.