Periodontitis is a bacterial infection. It appears in a generalised form but more often appears in local areas in a patient's mouth or is reduced to localised areas by mechanical treatment. Periodontitis lends itself well to treatment by means of a controlled local delivery system using an antimicrobial agent. Several products have been introduced or are in the process of clearing regulatory agencies. It is the goal of all local delivery systems to deliver high concentrations of an antimicrobial directly to the site of the periodontal infection. Concentrations of medication can be achieved considerably higher than could be obtained with systemic administration, while the systemic uptake of the medication is minimal. Five local delivery systems (tetracycline fibre, doxycycline polymer, chlorhexidine chip, minocycline ointment and metronidazole gel) are now available. Techniques for their use and the supporting scientific evidence are presented and indications for the use of the various systems are also discussed. These local delivery systems offer the clinician additional therapeutic procedures to aid in the treatment of the chronic inflammatory periodontal diseases.