It's for two guinea pigs, the biggest cage I could fit into my last house, I've since moved and no longer have a garden/run so an outdoor home isn't really suitable. I don't think my cat would attack the piggies as when they have the run of the lounge, she's interested but thats it, (loves watching my hammie in her wheel but has never attempted to get at her) but still, i wouldn't like to leave them alone together for long. I had thought about keeping the cat separate when I'm not around but the way my flat is divided this would not work either. thanks for your suggestions though, I will work out a way of giving them more room, i'm just not sure how yet!