These dogs are bred primarily for sport and as service dogs. They excel as police, military and drug/bomb detection dogs. If you seriously want a working dog, or one that can be competitive in sport, these are the lines you would consider first. They are less likely to show the conformation typical of show lin es, but many show excellent structure and are powerful and athletic. Sable, black and bicolour are typical, though black & tan also appears. Some show too much drive and aggression to be family or guide dogs, but many are suitable for any purpose.