Methods and devices for emitting volatile materials are disclosed. In some embodiments, methods and devices for emitting two or more fragrance compositions are disclosed. In one non-limiting embodiment of a device, the device has a housing, and the housing is supported on an electrical outlet by a plug at least indirectly joined to the housing. The device contains a first volatile composition and a second volatile composition. The first volatile composition is emmitted in an alternating period relative to said second volatile composition. In one embodiment of the method, the volatile compositions are alternately emitted during periods that are greater than 15 minutes and less than 2 hours.