A continuously operating spinning disk reactor (SDR) displayed distinct advantages over batch processing techniques when several commercially relevant processes for the manufacture of pharmaceuticals as test reactions were investigated. It proved to be a useful tool for revealing intrinsically fast kinetics as well as for optimizing processes with such kinetics. Very encouraging results were achieved for a phase-transfer-catalyzed (ptc) Darzen's reaction to prepare a drug intermediate and the recrystallization of an active pharmaceutical ingredient (API). In comparison to presently used batch processes, the ptc reaction resulted in a reaction with 99.9% reduced reaction time, 99% reduced inventory, and 93% reduced impurity level. The recrystallization yielded particles with a tight particle size distribution and a mean size of around 3 mu m. Reactor modeling was in good agreement with the experimental results and highlighted the advantages of the process-intensified equipment,with a production capacity of around 8 tonnes/year.