Abstract: A system for dispensing a pest attractant or repellent into a surrounding environment, comprising: a main reservoir for storing a fluid; a control volume coupled to the main reservoir, a first flow restrictor arranged to regulate a flow of the fluid between the main reservoir and the control volume; a second flow restrictor arranged to regulate a flow of the fluid out of the control volume; and, an evaporation medium positioned at or downstream of the first flow restrictor, wherein at least one of the first and the second flow restrictors is a controllable flow restrictor, and wherein the system further comprises electronically controllable actuation means for actuating the controllable flow restrictor.