Australian Institute of Refrigeration, Air-conditioning and Heating (AIRAH) has released the Building Simulation Procurement Guidelines, a free online resource for building simulation, in partnership with the Green Building Council of Australia, A building simulation is a computational model that approximates the performance of an actual building in practice, for energy consumption, thermal comfort, daylight or ventilation. A simulation has inherent limitations, functions as a valuable tool to inform the design process, and assesses a building design for benchmarking, rating and compliance. The topics covered include understanding the building simulation process to getting the most from a simulation. To access the free Building Simulation Procurement Guidelines, go to the ‘resources’ tab of www.airah.org.au and click on ‘technical resources’.