The article Chemical, Electrochemical, and Photochemical Catalytic Oxidation of Water to Dioxygen with Mononuclear Ruthenium Complexes (ChemSusChem 2011, 4, 197-207), co-authored by Stephan Roeser, Pau Farràs, Fernando Bozoglian, Marta Martínez-Belmonte, Jordi Benet-Buchholz and Antoni Llobet, has been highlighted on the front cover of Chemistry & Sustainability (ChemSusChem).The front cover of this special issue on Photocatalysis highlights research by Prof. Antoni Llobet and co-workers. In their Full Paper, they report on the oxidation of water to dioxygen with mononuclear ruthenium complexes as catalysts. The oxidation can be induced either chemically, electrochemically, or photochemically; the thorough investigation thus reveals the versatility of these complexes.