In this article, different microchemical plants for the synthesis of polymers and copolymers composed of microdevices are described and commented. Owing to their unique characteristics, microdevices allow rapid heat removal and mixing. This significantly improves the control over the polymerization by reducing or eliminating mass transfer limitations and hot spot formation. As a consequence, macromolecules with better controlled characteristics (eg, specific molecular weights and narrower molecular weight distributions), compositions, and architectures are obtained. Most common microdevices include microchannel-based and microtubular reactors used for heat-sensitive reactions. Micromixers are also an important class of microdevices from which polymerization processes sensitive to reactant mixing can benefit. The typical few milliseconds mixing achieved in these micromixers, facilitating a fast and efficient temperature control, together with the easy operation at high temperatures (and pressures) allow for new operating process windows (eg, high temperatures combined with short reaction times, higher reactant concentrations) and selective reaction pathways. Thus microdevices can produce higher yields and selectivity than batch technologies. Therefore, these microdevices are the element of choice in the intensification of polymerization processes with the hope to be implemented for chemical production after scaling-out. In addition, microdevices are also useful tools for high throughput experiments to generate a number of (co)polymers and to rapidly assess the influence of different process parameters.