In a call center with automatic answering, the availability of an agent is verified in order to prevent open connections when the agent unexpectedly leaves his or her station and fails to give proper notice. Verification may be provided by sensing speech activity of the agent when greeting a calling party or in response to an incoming-call signal. In other embodiments, verification may be provided by checking an audio device allocated to the agent, for example checking whether the agent is wearing his or her headset, or whether the headset is operably connected to the call center.