The objective of this paper was to provide a critical analysis of data generated by several previously completed projects and evaluate the rationale for establishing minimum disinfectant residuals at an operational level for utilities to use as guide values. An appropriate secondary disinfectant should be ranked on the basis of residual stability, biofilm control, direct toxicity, and disinfectant byproduct formation (DBP) (Trussell, 1999). These critical factors form the basis for the assessment presented in this paper, in which data is summarized from a culmination of full-scale and pilot-scale studies conducted at Dalhousie University over the past 5 years. In particular these studies have focused on three potential secondary disinfectants: chlorine, chloramines and chlorine dioxide and their impacts on E. coli inactivation in distribution systems, corrosion, DBP formation and water quality changes due to nuisance parameters such as manganese. The ultimate goal of the research program is to understand the efficacy of these pathogens to prevent microbial contamination, while minimizing other water quality burdens, such as corrosion and DBP formation, during distribution. A brief summary of the three disinfectant options is provided herein for reference purposes. Includes 15 references.