Catios are a great way to let your cat enjoy the outdoors and fresh air with far less risk of predation, disease, or injury.  Catios can take many forms, from outdoor mesh ramps that connect to windows, to stand alone structures where you can put a cat during your own designated 'outside' hours. Effective catios are escape proof and predator proof (usually preventing digging in from the outside), but allow a stimulating outdoor environmenet where cats can watch (but not kill) birds, mammals, and insects. Catios can be bought pre-done, constructed, or DIY'd for a variety of budgets. There are also designs that are renter-friendly. Some people have even turned Ikea furniture into catios!

Seattle also has a local 'catio tour' that is put on by Catio Spaces annually. 

There are many ways to provided supervised outside time for you cat. Some people prefer to go outside to an open space with their cat like a courtyard. Others like to bring their cats in secure strollers or backpacks to allow cats access to fresh air and stimulating outdoor environment without the risk of them escaping. Supervised outdoor time can take many forms, but its important to make sure you are not near busy roads where cats could wander into traffic and watch out for wildlife nearby that could injure your cat, such as owls, hawks, coyotes, and raccoons.