A literature review was conducted to assess existing information on supplemental treatment of domestic water distribution systems to prevent the proliferation of Legionella pneumophila. This review explores some of the critical issues regarding discrepancies frequently observed between the efficacy of various domestic water disinfectants as evaluated in laboratory in vitro tests as compared with results observed in full-scale system applications. Secondly, the review summarizes domestic water disinfection technologies currently authorized or with the potential of being authorized in Europe and the United States. These technologies include inorganic oxidants (chlorine, chlorine dioxide, monochloramine, ozone, hydrogen peroxide), ionization (copper and/or silver), thermal procedures and ultraviolet radiation. For each technology, the principle of microbial inactivation, survival curves for various organisms, the method of application, the cost and advantages/disadvantages are reviewed.