A dual technology glass breakage detector for a security system that detects the breaking of glass in a window or door without generating false alarms caused by similar types of sounds. The dual technology glass breakage detector includes an acoustic sensor/audio processor for detecting a sound of breaking glass within a premises protected by the security system, and also a second impact sensor mounted on the glass window or door to verify that there was a physical/mechanical impact to the glass window or door before the security system annunciates an alarm signal.