The design process is divided into seven major parts: general information, system boundaries and configuration, system operation, optional telephone service features, telephone lines, call answering and transfer equipment, and personnel. Each division contains the steps necessary in the design process. All the technical and operational components of a basic 911 system are described, and detailed examples showing how to compute the required numbers of telephone lines and personnel are given. The procedure for designing a selectively routed 911 service system is also presented, including in the discussion only unique selection routing design activities and those technical and operational components that are specific to a selectively routed system. Procedures for obtaining a cost estimate (initial and recurring costs) are detailed and cover the costing of both basic and selectively routed 911 systems. Several nontechnical 911 system design areas are addressed, including system management alternatives, system finance alternatives, and a process for performing a cost-effectiveness analysis of alternative systems. Companion documents concerning public education and staff training are briefly described. Tables for determining the number of call answerers required per shift and 911 system design and costing worksheets are appended. A glossary, footnotes, additional tables, figures, and nine references are included.