No small concrete pens for our dogs...grass/gravel 30' runs with access to the heated/cooled indoors. The runs are usually open to each other with adjoining gates so the dogs can enjoy each other's company. They also have a 2 acre exercise yard behind the dog house where they work and play and the swimming pool where they swim. We are hoping to get a pond built soon on our farm a mile down the road...that will take care of dog hair in the pool!