The Sussex Spaniel is a breed of dog developed in Sussex in southern England. It is a low, compact spaniel and is similar in appearance to the Clumber Spaniel. They can be slow paced, but can have a clownish and energetic temperament. They suffer from health conditions common to spaniels and some large dogs, as well as a specific range of heart conditions and spinal disc herniation.
First bred in 1795 in Hastings, East Sussex for specific hunting conditions, they nearly became extinct during the Second World War. They are now more popular in the United States than any other country and are recognised by all major kennel clubs. Notably, a Sussex Spaniel won the best in show in 2009 at the 133rd Westminster Kennel Club.