This paper covers the main medical applications of artificial membranes. Specific attention is given to drug delivery systems, artificial organs and tissue engineering which seem to dominate the interest of the membrane community this period. In all cases, the materials, methods and the current state of the art are evaluated and future prospects are discussed. Concerning drug delivery systems, attention is paid to diffusion controlled systems. For the transdermal delivery systems, passive as well as iontophoretic systems are described in more detail. Concerning artificial organs, we cover in detail: artificial kidney, membrane oxygenation, artificial liver, artificial pancreas as well as the application of membranes for tissue engineering scaffolds and bioreactors. This review shows the important role of membrane science and technology in medical applications but also highlights the importance of collaboration of membrane scientists with others (biologists, bioengineers, medical doctors, etc.) in order to address the complicated challenges in this field.