A lot of assistance dog programs use Golden Retrievers and Labradors. They have many of the characteristics that make for a good service dog. However, there are examples of many other breeds that have been successfully trained as service dogs. Although the needs of the person may determine the ideal size of the dog, the work they do generally requires a dog to be a reasonable size. Small dogs will struggle to pick up and present objects in a suitable way, large dogs are hard to put under a table in a restaurant or out of the way on a bus or plane. A good service dog is not protective, is people orientated, not overly active, confident but not dominant or submissive. Service dogs should not require complex grooming as this could be a problem for their owner.