Abstract: The present invention provides a system for dispensing a volatizable material when needed. In an exemplary embodiment, the system includes a sensor to detect malodors, where the sensing of a malodor is used to activate fragrance emission when needed, and not, when not needed. In an exemplary embodiment, the sensor is able to distinguish between different malodors in different locations, such that a single system may be used in different locations. In an exemplary embodiment, the system includes an indicator configured to indicate to the sensor the type of malodor to detect to activate fragrance emission. In an exemplary embodiment, the indicator is included with the container of volatizable liquid, either mechanically or electrically.