Process Intensification is a technology concept that attempts to increase the processing efficiency and throughput of a chemical plant. Separating reactors – chemical reactors that remove product from a reaction as it is formed – are an expeditious means of process intensification to reduce capital and operating costs, particularly where the reaction is equilibrium limited, and many commercial scale processes are in operation. Cyclically operating separating reactors are a development of this technology, which offer a number of benefits in operation. The technology has advanced to pilot scale, available "off the shelf", with several commercial scale applications under investigation.Cyclically Operating Separating Reactors is a critical examination of the relevant literature, aimed at establishing the magnitude of performance improvement available with this type of reactor with respect to systems in which the reactor and separator are separate units. The adequacy! of present models is considered by comparison of simulation and experimental studies, and gaps in understanding or experimental verification of model predictions are identified.