This article describes the diagnosis, pathogenesis and treatment of food allergy (FA), defined as “all immune-mediated reactions following food intake.” FA pervasiveness in pets is unknown with no breed, sex or age bias. The paper identifies two main developmental risk factors , the most likely immunologic mechanisms and primary food allergens. Usual clinical signs which appear after two years of exposure to the offending allergens, are non-seasonal pruritus and/or gastrointestinal disorders, sometimes with parallel allergic diseases. Reliable diagnosis is through dietary elimination with provocation testing to identify causative food component(s). Treatment is by avoiding the offending food component(s).