Working Line Breeders. A working line breeder focuses on breeding dogs specifically for their ability to perform certain tasks. While a show line breeder breeds a dog for his conformation (how closely it matches the breed standard), a working line breeder breeds dogs that show a strong aptitude for the type of work the breed was originally created to perform. Working line breeders typically breed dogs that have the right aptitude, serious attitude and behavioral traits for the job it was bred to do. You might wonder why you need a working line breeder to breed for specific behavioral characteristics. Don't all dogs of the same breed share the same aptitude, stamina, and work-related attributes? Actually, they don't. Without breeding targeted for these behavioral characteristics, a dog's natural working instincts and characteristics may fade or show in inappropriate ways over several generations. For example, a Border Collie that hasn't come from a working line breeder may still naturally chase and be able to learn how to herd sheep. However, over many generations of breeding for confirmation to a breed standard, the herding instinct may become 'diluted'. In other words, the dogs don't have strong herding instincts because over many generations they have been bred to 'look right', but lack the real aptitude and temperament of a working Border Collie. If enough Border Collies with a weak herding instinct are bred, the herding instinct in the line gets weaker, and the dogs may show very little aptitude or interest in herding. Dogs with a weakened or diluted herding behavior may express this as an increased prey drive, since the ability to herd is a modified prey drive. This can cause the dogs to nip, bite or even outright attack livestock, small, fast-moving animals and children, because the herding instinct has been corrupted. At the very least, you may get a herding dog that can't herd. At worst, you may get a herding dog that harms livestock and is a liability on a farm. Therefore, it's important to select a working line breeder if you want a dog that doesn't just look the part, but can actively do the work you have in mind for him. If you want a dog for hunting, herding, assistance dog work, or other working dog applications, look for a working line breeder. Likewise, if you want a dog to participate in dog sports or other strenuous competitions, a working line dog is more likely to have the temperament, aptitude, more serious attitude, and behavioral traits you need. The strong instincts and desire to work in working line dogs can be a liability in a companion dog. If you get a working line dog but then don't provide the dog with enough work, or proper training, his strong instincts and drive can make him very difficult to control. Don't get a working line dog unless you're committed to providing enough exercise and training. Like show line breeders, working line breeders may have dogs that aren't quite qualified to be 'working' dogs but may still make excellent companions. In fact, working dogs without the strong working instinct may be the perfect companion animals, because they're bred for their behavioral characteristics - not how they look. If you're not looking for a working dog, you may still contact a working line breeder to determine whether they have any dogs that might be suitable as companion animals. Also like show-line breeders, performance-line breeders may seem overly selective in placing their dogs. They may require extensive screening processes, and working-line dogs will probably be more expensive than pet quality dogs.