Summary: This module is a practical tutorial of the use of MATLAB and SIMULINK as simulation tools for energy efficient building operation. A complete walkthrough of the software and explanations of the different libraries and modules is provided in a hands-on session. This software is a state-of-the-art tool ecosystem with proven capabilities to flexibly accommodate most mathematical and numerical methods for energy modelling and multi-domain building operational problems. The modelling style of the software is equation based with a graphical block editor. The results can be integrated into other software for control and feedback loops to real systems e.g.: HVAC controls. The tutorial will be illustrated with two case studies: (1) a domestic scale heating system and (2) simulation of a smart grid project.