Data communications for a Water Quality Surveillance and Response System (SRS) is the means of transmitting data between remote monitoring sites and a drinking water utility's control center. Within an SRS, the Enhanced Security Monitoring (ESM), Online Water Quality Monitoring (OWQM), and Automated Metering Infrastructure (AMI) components typically include data generated by SRS equipment located at remote utility locations that is transmitted to the utility control center. When alert conditions are detected, utility personnel are notified via a user interface screen, email, or text message to initiate a response and, in some cases, utility personnel will transmit data to equipment at the remote sites as part of their investigation of SRS alerts (e.g., initiate collection of a water quality sample or position a video camera to observe an intruder). This publication describes the process of developing evaluation criteria, describes commonly available communications technologies, provides an overview of SRS component requirements for communications systems, describes the process of selecting a communications system, includes design and implementation guidance, and describes innovation in communications systems.