assembly wasn't what I would call quick and simple, but it wasn't terrible either. really REALLY great quality cage, tons of space, using it for my 8 female rats and they love it. only needed minor modifications to fit the litter pan ontop of the floor instead of under it so they aren't standing on bars all the time. The hammock was a nice addition too, very sturdy and comfy. Overall I'd recommend this cage as an excellent alternative to a double critter nation.