A building management system (BMS) is a control system that can be used to monitor and manage the mechanical, electrical and electromechanical services in a facility. Such services can include power, heating, ventilation, air-conditioning, physical access control, pumping stations, elevators and lights.

A very basic BMS consists of software, a server with a database and smart sensors connected to an Internet-capable network. Smart sensors around the building gather data and send it to the BMS, where it is stored in a database. If a sensor reports data that falls outside pre-defined conditions, the BMS will trigger an alarm. In a data center, for example, the BMS might trigger an alarm when the temperature in a server rack exceeds acceptable limits.

Depending on the system, BMS software can be installed as a standalone application or it can be integrated with other monitoring programs. More advanced BMSes can monitor and manage a wide range of building services across multiple platforms and protocols, providing facility administrators with a single, shared view of the facility's operations.