Much like humans, every breed of dog has some sort of health issue. The Clumber Spaniel is no exception.
Good breeders do their best to breed healthy dogs by having various screening tests performed on their dogs before they are bred as well as keeping track of problems in their dogs’ bloodlines. As much as they would like to do so, no reputable Clumber breeder can offer a lifetime health guarantee, or promise that their puppies will not have hip dysplasia or other hereditary health problems. You can increase the odds that your Clumber Spaniel will not only be happy but also healthy and structurally sound, however, by asking about health issues and only obtaining your puppy thorough a breeder who is addressing them responsibly.
It is also important to follow your breeder's advice carefully. Since the Clumber population is relatively small, long time breeders have vast experience with their breed and often have encountered many more issues than can possibly be seen in a veterinary office where a practice may never have seen a Clumber Spaniel. In addition, The 'Dear Vet' letter provided here explains in detail many of the health issues encountered in this breed.
Please also visit the Clumber Spaniel Health Foundation website to learn more about Clumber health issues.