Process intensification (PI) provides great opportunities to drastically improve the performance of chemical processes within many branches of chemical industry including the pharmaceutical industry. Crystallization is an important purification and separation technology within many pharmaceutical processes. This paper provides a systematic review on the recent developments of PI approaches that are applicable to pharmaceutical crystallization. The various approaches are categorized according to the four fundamental PI domains (space, time, function, energy) that have been proposed in literature. Each approach is illustrated with examples from literature with an emphasis on the opportunities to intensify pharmaceutical crystallization processes. Finally, some thoughts on the level of maturity for industrial implementation of the various approaches are provided.