The possible place and role of different membrane processes for post combustion carbon dioxide capture are reviewed and discussed. In a first step, the interest and limitations of membrane contactors in order to achieve intensified CO2 absorption in a chemical solvent are briefly exposed. Membrane based separation processes are presented and discussed in a second step, with two major strategies: low selectivity, high permeability materials which require multistage processes, and chemically reactive, high selectivity membrane materials which could possibly achieve the target CO2 capture process in a single stage. A special emphasis is put on materials and design challenges. Unexplored issues (target CO2 purity, cost curves, hybrid processes, role of water, minor components) are finally exposed as major research targets. (C) 2011 Elsevier B.V. All rights reserved.