We have taken our dog, Sophie, a few times now to the dog park at the Tempe Sports Complex. It is absolutely fabulous once you find it! The Complex is huge, so the first time we went, we parked on the opposite side where the dog park is located since we didn't know better. My only problem is that there are no signs directing you at the Complex where everything is. Since then we have figured out exactly where the dog park is and the best place to park (hint: turn onto Carver Rd and you can park in the lot right in front of the dog park. The Tempe Police substation is on the corner).
The dog park itself is absolutely huge-much, much bigger than the one we used to go to in Ohio. The times we have been to the park, there have been about 15-20 dogs which is a good amount. There are benches for the owners to sit on, as well as some picnic tables. Additionally, there are bags for dog poop and faucets for water, so if you forget bottled water it's no problem. All of the dogs and owners we have met at the park are very friendly and nice. We have not yet encountered an aggressive dog, and all of the owners watch their dogs very well.
Sophie has so much fun running around and playing and is always worn out by the time we get in the car to come home. She even found the last remaining puddle from the rain last week and managed to get muddy :)