If you live in the Greater Phoenix area, chances are there's a dog park within 20 minutes of your home where you can take your dog for a romp off leash. These are fenced dog parks. Keep in mind that dog park configurations may change from time to time, as will the amount of grass in the park depending on the season and maintenance of the dog park. To locate a dog park near you, use this zoomable map of Greater Phoenix dog parks.

You can find a description of the dog parks here:

Dog Park Rules and Etiquette
Dog Park Description: Avondale, El Mirage, Glendale, Goodyear, Peoria, Surprise
Dog Park Description: Casa Grande, Tempe, Mesa, Chandler, Gilbert, Florence, Queen Creek
Dog Park Description: Scottsdale, Fountain Hills
Dog Park Description: Phoenix, Maricopa