Building Energy Management Systems are used to improve energy efficiency by monitoring building temperature inside and outside buildings and controlling the boilers and coolers. Energy efficiency is a major cost issue for commerce and industry and of growing importance on university syllabuses. Fully revised and updated, this text considers new developments in the control of low energy and HVAC systems and contains two new chapters: Commissioning, sick building syndrome and occupant feedback and natural ventilation as well as new material on Fuzzy Logic and Intelligent Buildings. Written for practising engineers (essential for control engineers) and energy managers as well as essential reading for courses in building services and environmental engineering.