This paper gives an overview of the recent developments and state of the art of hollow-fiber membranes, including the preparation, applications and development trends of the membranes. The methods for the preparation of hollow-fiber membranes are mainly melt spinning and solution spinning. Prepared via melt spinning, most of commercial microporous hollow-fiber membranes have been achieved by thermally induced phase separation. The dry/wet solution spinning process produces either a nonporous (integrally-skinned) or microporous hollow-fiber membrane via the nonsolvent induced phase separation process, depending on the length of solvent evaporation time (in air). The applications have included membrane contactors, supported liquid membranes (SLMs), SLMs with strip dispersion, artificial kidney, gas separations, pervaporation, ultrafiltration, and microfiltration. On development trends, environmentally friendly solvents and highly thermally stable and solvent resistant materials are being used recently in the preparation of hollow-fiber membranes. Hollow-fiber membranes with improved properties are being developed, and they not only will enhance and widen existing applications, but also will speed up the development of emerging applications and will find and create new applications.