For reactive crystallization of pharmaceuticals that show rapid reaction rate, low solubility of active pharmaceutical ingredient, hence large supersaturation, it was found in a recent study that a process design that integrates an impinging jet mixer and a batch stirred tank, the former to achieve intensive micromixing prior to reaction and crystal nucleation and the later to immediately disperse the formed nuclei or small particles to minimise aggregation but promote crystal growth, has produced high quality crystals. The current investigation studies the hypothesis that due to the short processing time of reactive crystallization, the impinging jet mixer -stirred tank design can be made to operate in continuous mode. The new design combines an impinging jet mixer for feed introduction and reaction, and a continuous stirred tank reactor (CSTR) and a tubular reactor for crystal growth. Study on reactive crystallization of sodium cefuroxime (an antibiotic), using firstly in a 1L CSTR then scaled to 50L CSTR, found that the new design has produced crystals of higher crystallinity, narrower particle size, and improved product stability, than the conventional batch crystallizer.