I built this birdhouse in October, 2004. I found the plans on a website. It is intended to be suitable for Kestrels or Screech Owls. I placed the birdhouse about 20 feet up in a suitable tree. Then I sat back to wait for the Kestrels to start moving in. Amazingly, I saw a Kestrel near the birdhouse within 24 hours of the time I set it up.