Main motivation for the use of a polymer electrolyte membrane fuel cell (PEMFC) in traffic applications is its significant higher vehicle efficiency compared to internal combustion engines (ICE) especially under low-load operation. Hydrogen is the ideal fuel for PEMFCs as it yields the highest level of fuel cell performance. Three different applications for gas permeation inside a fuel cell system have been investigated: water recovery, hydrogen purification, and oxygen enrichment. The focus was on the analysis of the technical feasibility and the availability of capable membranes on the pilot-scale size for each application.