Continuous operations can be used for the efficient scale-up of many processes that cannot be carried out through batch operations. Rapid reactions with reactive intermediates and products can be scaled up in the laboratory using continuously stirred tank reactors (CSTR) and plug flow reactors (PFR). Continuous processing in small reactors allows for better control of exothermic processing, creating a larger margin of safety for scale-up. This review also discusses the advantages of continuous processing for thermochemical rearrangements, immobilized catalysts, and microwave, photochemical, electrochemical, and sonochemical processes. Many of these continuous operations can be performed using equipment readily available for the laboratory, and can be readily scaled up in the laboratory and pilot plant.