In recent years, membrane technology has improved the control of protein crystallization and post-crystallization treatment of protein crystals. Many advancements have been achieved regarding solvent evaporation control, heterogeneous nucleation modulation, diffusion of ligands, and the attainment of a protective environment from the combination of membranes with hydrogel materials. Indeed, membranes allow for finer control of the supersaturation rate and nucleation at lower degrees of supersaturation while also enhancing crystallization kinetics, providing greater stability, and decreasing crystal handling during post-crystallization. This comprehensive review addresses the concept of membrane-assisted crystallization with a particular focus on proteins and the impact of the process on the quality of crystal diffraction. Furthermore, it advocates for the benefits of combining membranes with microfabrication technologies and encourages the innovation of new membrane-devices with high-throughput for crystallographic purposes.