MarcoPolo-R is a sample return mission to a primitive Near-Earth Asteroid (NEA) selected in 2011 for the Assessment Study Phase of M3-class missions in the framework of ESAs Cosmic Vision (CV) 2015-2025 programme. The phase A study started at the end of 2012 and will proceed throughout 2013. The final selection by ESA will occur in February 2014. MarcoPolo-R is a European-led mission with a possible contribution from other agencies. MarcoPolo-R will rendez-vous with the primitive NEA 2008 EV5. Before returning a unique sample to Earth, the asteroid will be scientifically characterized at multiple scales. MarcoPolo-R will provide detailed knowledge of the physical and compositional properties of a member of the population of Potentially Hazardous Asteroids (PHA), which is an important contribution to mitigation studies.