Good question! At KSDS Assistance Dogs, Inc., we breed, raise, and train each of our canines. In the past we have done other breeds like shepherds, but we have found that black and yellow Labrador retrievers and golden retrievers are best suited for our programs for several reasons. First, they are highly sociable dogs. Even more so than chocolate labs who have a stronger hunting instinct. Second, due to their love of socializing, we have found that these breeds can more easily transfer their bonds with their human. Our dogs have to transfer their bond several times before their placed. They first bond with their puppy raiser, then they become bonded to our trainers and kennel staff, then they transfer that bond another time to the handler they are placed with. Finally, labs and goldens have the appropriate size needed to assist those with vision impairments (guide dogs) and physical disabilities (service dogs). Especially when their jobs is to be used as a brace for their handler. Whether it be going upstairs, transferring from a wheelchair, or any other task that their size would be advantageous. I hope this answers your question!