The course relates surface characterization methods to associated physico-chemical phenomena of relevance in (bio)engineering. Three levels of characterization are covered, through in-depth study of three families of techniques. Part A: Chemical analysis of surfaces with an emphasis on X-ray photoelectron spectroscopy: principle, instrumentation, qualitative and quantitative aspects. Part B: Gas adsorption and its use to characterize the texture of solids: physical and chemical adsorption, adsorption isotherms, quantitative approaches. Part C: Electronic and scanning probe microscopies, emphasizing atomic force microscopy: instrumentation, imaging and force spectroscopy modes. The course combines the study of concepts, illustrations with practical examples and demonstrations on the instruments.