J.C. Conesa entered the permanent staff of ICP in 1979. He was ICP Vicedirector, then ICP Director, being now ICP Ad Honorem Professor. He was first in Spain using SR techniques to study heterogeneous catalysis, and first in CSIC to use quantum calculations to understand them. He is expert in XPS and FTIR (including operando), EPR and UV-Vis-NIR. He analyzed CeO2-supported metals and oxides, firstly for car depollution and later for H2 production technologies. He keeps continued interest in photocatalysis and photoactive solids. He belongs to the Steering Committee of AMPEA, a Joint Programme of the European EERA devoted to sustainable energy. His more than 200 articles and book chapters have received more than 9900 citations.