SMSI is a surface phenomena in which the migration of partially reduced oxide species, from the oxide support, covers the nanoparticle and thereby alters the chemisorption and catalytic properties. It can give rise to desired synergistic effects and increased selectivity. Now, using in situ TEM combined with other analytical techniques and theoretical modelling, researchers at ETH Zurich have been able to create a real time view of the SMSI phenomena.