Periodontitis has two distinct but interconnected etiologic components: periodontopathic bacteria adjacent to the periodontal tissues, and host-mediated connective tissue-destructive responses to the specific causative bacteria and their metabolic products. Although past and existing therapies have focused primarily on the causative microbial challenge, the host component of periodontal destruction has recently been intensely studied. New treatment strategies that focus on attenuating destructive host responses are emerging. Host modulatory agents, when used adjunctively, may enhance clinical therapeutic responses and make these responses more predictable in the susceptible host. The ongoing development of safe, effective pharmacotherapies that specifically target host response mechanisms, and the introduction of such pharmacotherapies as adjuncts to traditional, antimicrobial interventions may represent a new, integrated approach in the long-term treatment and management of this chronic disease.