AbstractContinuous reactor systems find important applications in the production of sythetic polymer latexes and increased production rates are providing additional incentives for the development of new continuous systems. The fundamental factors that should be considered in the development of continuous processes are reviewed in this paper. Particular emphasis is placed on exploring the differences between batch and continuous reactors and why these difference can lead to different latex product, even if the same recipe is employed. These factors make the task of designing continuous reactor systems based on batch research and development very difficult and risky. Thus it is recommended that small‐scale continuous reactors be employed early in a product/process development effort if that effort is likely to lead to a continuous commercial process.The published literature on continuous emulsion polymerization reactors has been reasonably active in the past ten years. Our understanding of the chemistry and reactor modelling has been advanced but a number of areas for fruitful research remains. Some of these problems are reviewed and directions for new efforts are suggested.