We have our gliders in what's basically a bird cage, but the bars are only 1/2 inch apart, and we haven't had any problems. At our house, the predators (2 dogs and a cat) live downstairs, and the "prey" (2 sugar gliders, 2 rats, and one rabbit) live upstairs. We keep the downstairs door closed. In the evening, when the gliders wake up, we let them out in the closed off upstairs landing area to play. They run and hop all over the place and chase each other around. The only thing we don't like about this arrangement is when we're tired and they're not, and it's hard to get them to go back in the cage. Usually, a little food helps.