Vaccine research in periodontal diseases is still in its infancy. The complexities in the etiopathogenesis of the periodontal diseases have been the prime obstacle in the hunt for vaccine. Among some 300 species of bacteria involved in subgingival plaque, 5-7 species have been implicated in the etiology of periodontitis which might play an important role as primary pathogens. A new milestone was achieved after the prime pathogens, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, were implicated in the etiology of periodontal disease. Now, vaccine research has shifted toward identification of valid antigenic targets/molecules of P.gingivalis and A.actinomycetemcomitans involved and thus induction of suitable immune response.