ADS (the American Driving Society) as well as FEI (International Equestrian Federaton) have designed a series of tests for each level of driver. Tests are driven in a specified size arena that is usually 40 X 80 or 40 X 100 meters. Sometimes a smaller size is used for very small equine (VSE-39 inches and less). ADCS commonly uses a 30 X 60 meter arena for VSE.
Tests include an enter down centerline at the trot, halt and salute the judge, trot and walk circles of various sizes in both directions at particular spots in the arena, working trot and lengthened trot down sidelines or across the diagonal, and a final halt and salute. The exact pattern and order of elements will change with each test and depending on what level the test is. Some Intermediate and FEI level tests include a canter.
Examples of Driven Dressage tests can be found at the ADS.
In addition to Dressage at an ADT, ADCS offers judged dressage tests as part of our Pleasure Show, and has at times offered Dressage only competitions.