Local antimicrobial therapy has become an established part of the armamentaria for the reduction of plaque and gingival inflammation in the treatment of gingivitis. The antimicrobial agent chlorhexidine possesses most of the characteristics of the ideal antimicrobial. That is, it is safe; clinically effective in reducing plaque and gingivitis, has substantivity; affects the pathogenic flora and is acceptable in terms of taste, cost, and ease of use. Recently a new approach using local delivery system containing antibiotic or antiseptic drugs has been introduced. These systems allow the therapeutic agents to be targeted to the diseased site with minimal systemic effects. The new approach also addresses the critical concern of unnecessarily exposing the patient to large amounts of systemic antibiotics which can result in bacterial resistance. In the light of the above facts, this clinical and microbiological trial is designed to compare the treatment outcome of the time tested scaling and root planing with adjunctive use of chlorhexidine chip ( PeriochipTM) along with scaling and root planing in the management of moderate to deep periodontal pockets of chronic periodontal cases.