I live in a very swampy area prone to TONS of mosquitos.  In fact, sometimes I haven't been able to open my front door without all lights being off and first spraying bug spray.  It's awful.  So I put this thing about 20 feet from the door and set it up to go on for an hour after dark using a timer (not included).  There are so many dead bugs on it, I'm amazed.  Really works.  And unless the mosquito population is low this year or I'm forgetting when they actually come out, it's cut back significantly on my "house entry" troubles.