The levels are even and straight up. Hard for the cats to jump, they have to try and jump straight to the top. If they try to get on the first level, the shelf above is the same size, they hit their heads. Not stair-stepped at all. My cats will not use it. I am very disapointed and so are my cats!!! Looks stairstep, but is not, shelves are same size, and is top heavy.