A case of Oral Allergy syndrome or Pollen-Food Allergy Syndrome is briefly discussed. The clinical characteristics, diagnosis, pathogenesis, and management of this syndrome are discussed followed by clinical pearls and pitfalls for the practicing allergist. Symptoms generally occur with the ingestion of raw fruits/vegetables and nuts; cooked foods are not a problem. Symptoms are caused by a heat-labile protein in fruits, vegetables, and nuts that cross-reacts with proteins in aeroallergens. Cross-reactive proteins share homologous epitopes, and several groups with similar homologous proteins have been identified; many of these groups are referred to as pathogenesis-related proteins.