My cat, Jack loves to climb and loves to lie in his window perch...so I decided to see how he'd like his own 'tower'.  I have it sitting in front of my sliding glass window and he spends hours watching the outdoor cats, squirrels, and birds.  The first day I assembled it he was on the top perch within an hour and a bit later I heard a strange noise and realised he was using the scratching posts... A definite great addition to his and my life!