Abstract: In order to achieve effective control of pests (such as insects and rodents) in residential and commercial buildings, a permanently installed pest control system is disclosed which is particularly adapted for incorporation into existing structures without substantial modification. The system includes an exterminating liquid supply subsystem and an exterminating liquid distribution subsystem. The supply subsystem includes a replaceable exterminating liquid reservoir, an electrically driven pump and switch means (which may include a time clock and a short term timer) coupled to a source of electrical energy to selectively energize the pump.