My newfoundland breeder offers a lifetime guarantee against any genetic "crippling hereditary defects. Crippling being defined for these purposes as the inability to function as a good pet and companion". This means that if my dog comes down with hip dysplasia or PRA, both of which would limit the functions of my dog greatly, I can either get a full refund of the purchase price, or I can get my puppy replaced if the condition is so bad that euthanasia is required. My breeder's health guarantee has been described by other newf breeders and owners as one of the best in the business. I love it.