Abstract
In this contribution, I first briefly summarize some of the recent advances relevant for the investigation of heterogeneous catalysis with Ambient Pressure X-ray Photoelectron Spectroscopy (APXPS). In the second part, two examples of the research done at the CIRCE beamline of the synchrotron ALBA are described: CO oxidation on a model curved crystal Pd(111) catalyst and methanol steam reforming on powder bimetallic supported catalysts, PdCu/ monoclinic and cubic zirconia.