After reading a bunch of reviews I ordered this for my two housecats to ease the transition into a new home. I have had the Feliway diffuser plugged in for the last month and have not seen any change in the behavior or disposition in my cats. Vertical scratching and irrationally fearful behavior when new visitors arrive still persist. It has definitely not helped "comfort" the cats in the ways advertised. Of course I don't expect miracles but I expected to see some change. Now that 30 days have gone by I am reluctant to spend another $20 to refill the diffuser. Maybe a Glade plugin will work just as well!