Fifty-one patients with clinical history of dog allergy were skin prick tested with eight individual standardized dog breed-allergen preparations, one mixed breed-allergen preparation (Poodle/Alsatian), dog-serum albumin, and histamine hydrochloride, 1 mg/ml. All extracts were characterized by crossed immunoelectrophoresis and crossed radioimmunoelectrophoresis with a pool of sera from patients clinically sensitive to dog. The dog-breed extracts contained common antigens/allergens, as well as components represented only in one or two dog-breed extracts. The concentration corresponding 1000 BU/ml varied from 16 to 100 micrograms of protein per milliliter. The sensitivity of skin prick test was 67% to 88% for the various dog breed-allergen preparations, but only 18% for dog-serum albumin. Significant difference between the skin test response to different dog breed-allergen preparations indicating dog breed-specific allergens was obtained in 15% of the patients. There was no significant correlation between skin prick test results and symptoms related to a specific dog breed.