Oxides show vast variablitiy in electronic and chemical properties, which makes them ideal materials in a large range of technical applications. Often, surfaces and interfaces play a major role in the functioning of related devices and schemes. Our research group is devoted to investigating the fundamental properties of oxide surfaces, from complex reconstructions to the interplay between localized charges (‘polarons’) and chemical properties. In the talk, I will highlight a few recent results, which are all based on the fruitful interaction between experiments using surface science methods and ab-initio calculations.