The government of a Maryland county has applied the commissioning process in a new mixed-use, multiuser government facility. A comprehensive array of monitoring equipment was installed with the assistance of the local utility for the specific purpose of facilitating the commissioning of a state-of-the- art HVAC system for real-time monitoring of its performance. Specific lessons learned include - (i) points to monitor - how much is enough? (ii) software versus hardware - what to use and when (iii) reality check - who's interpreting the data? (iv) cross checks - is anybody watching? (v) air balance - helpful hints (vi) commissioning of thermal storage - is there any ice left? (vii) use of EMS in trending system performance.KEYWORDS: commissioning, air conditioning, ventilation, computer programs, monitoring, comparing, energy management, controls.