Adaptive polymersome systems have gained much interest in a wide variety of research fields, ranging from cell mimics to nanomedicine, because of their high stability, tuneable shape and size. Furthermore, polymersomes can be effectively transformed into nanoreactors via the incorporation of catalytic species. By employing polymersomes which are adaptive in structure and function the features of polymersome nanoreactors can be even further extended. In this review, we focus on recent impressive developments of smart polymersomes as functional nanoreactors with an emphasis on the type of adaptivity that is installed, which includes intrinsic permeability, stimuli‐responsiveness and self‐adaptivity. Moreover, particular attention is given to the utility of polymersome nanoreactors in vitro and in vivo, which paves the next step forward towards the engineering of artificial organelles as therapeutic materials.