Abstract: An emergency signaling system using the existing two-wire circuit (10) between a switch assembly (15) located within a dwelling and an externally mounted lamp housing (20) includes a switch (25) having an "off" position (27), a "normally on" position (28) whereby a lamp (55) is illuminated continuously, and an "alert" position (29) which activates a circuit (35) preferably included within the same protective enclosure (30) which contains the switch. The circuit (35) causes the current to the exterior lamp to be interrupted at a periodic rate, and it may also include as optional features an audible alarm (40) and a visual indicator (45) to identify when the alert feature is in operation. An adapter (60) is positioned between the lamp (55) and the existing lamp socket (50), and the adapter includes a circuit (75) responsive to the interruption of the current in the two-wire circuit to activate an audible alarm (65).