The process industry faces the challenges of intensified, global competition with increasing market dynamics. Modular, transformable production concepts promise a better adaption to these in the dimensions of throughput, product mix, and production location. In order to unfold the full potential, modularization and transformability have to be carried out not only on the plant and logistics level, but also on the apparatus level. Characteristics like setup and scaling concepts are discussed. Examples for modular apparatuses concerning the process engineering tasks of mixing, heat exchange, reaction and separation are presented and further research needs are derived.