A system for accurately detecting the unavailability of a call center agent that uses one or more agent sensors provided in the area of the agent's desk or station that are triggered when the agent moves into or out of the physical area in which he or she can answer calls. The agent sensor may be an external hardware peripheral device which communicates with a call center software application. The agent sensor operates to notify the call center application when an associated agent leaves their desk, so that the call center application can make that agent unavailable to receive calls as a result. When the agent returns, another signal may be sent from the sensor to the call center application indicating that the agent is again available to receive calls. The information gathered by the call center application from the sensor signals may be used to assist in report generation regarding call center agents, and to improve call center performance, since calls are not forwarded to agents that have stepped away from their desk, even for a brief moment.