Polymersomes provide a highly promising platform for mimicking biological membranes as well as for controlled delivery of various pharmaceuticals and biopharmaceuticals. The recent advancement has made it possible to prepare small to giant polymersomes spanning from nano- to microscales, stimuli-sensitive polymersomes that swell or collapse in response to an external or internal stimulus, chimaeric polymersomes that contain distinct interior environments separated from the outside by an asymmetric membrane, porous polymersomes with tailored permeability, biomimetic and targeting polymersomes that selectively deliver drugs, proteins, and/or imaging probes to the sites of action. In this Perspective, we will give a brief introduction to polymersomes, highlight recent design and preparation of several sophisticated polymersomes, and discuss future challenges.