chunks. And of course the poop is also lifted out. I put everything in plastic grocery bags and then put those bags in the outside trash can. This clumping litter -- I use Tidy Cats -- is fantastic, IMO. It leaves the boxes nice and clean and also odor free since you're removing just about everything deposited by the cat(s). And it lasts a very long time. As long as it's still fresh-smelling -- and it stays that way a VERY long time -- I just add new litter to the boxes when it starts getting a little low. I like to keep a substantial amt of litter in the boxes. I read once that cats like it to be about 3" deep. I asked my cat about that and he said, yes, that's a good depth for him. :-)