Despite much of the argument that has persisted through the years, distributed control systems (DCSs) and programmable logic controllers (PLCs) are not mutually exclusive technologies. When the end-use application serves as the basis for making a sound decision, the selection process becomes more efficient, and a more effective outcome results. This white paper provides general guidelines and highlights key considerations when choosing a control system platform. While the details of each application are critical to the selection process, use the 8-page white paper as a guide when designing, specifying, and implementing controller technology. The paper includes a comparison chart and block diagrams.