Flea allergy dermatitis is one of the most common causes of pruritus in dogs and cats. The degree of pruritus observed in the allergic animal varies widely and is dependent on numerous factors. Management of the flea-allergic patient is extremely frustrating for the owner and the veterinarian. Establishing an organized flea control program for use on the patient and in the environment will help to avoid frustration when dealing with this common ectoparasite of cats and dogs.