State-of-the-art in-situ analytical techniques enable us to investigate the structural and chemical properties of solid/liquid interfaces under realistic conditions, i.e., at room temperature and often under the influence of an applied potential and charge transfer. Our methods include electrochemical scanning probe microscopy and X-ray photoelectron spectroscopy. In addition, the corresponding product analysis methods, such as differential electrochemical mass spectrometry, gas chromatography and electrochemical infrared spectroscopy, provide direct information about reaction products and intermediates. In this way, reaction mechanisms can be elucidated holistically.