The German Pinscher is a medium size dog that is one of the oldest breeds of dogs going back to the 1700's. It came before the Doberman Pinscher and the Miniature Pinscher. Originally it was bred to hunt vermin as well to guard. The German Pinscher can grow to a height of 20 inches.
It's a really smart and intelligent dog. It's assertive and fearless which makes it a great guard dog. It requires a good amount of activity to keep it happy.