INTRODUCTION Heterogeneous Catalysis Aim of Catalysis Characterization Spectroscopic Techniques Research Strategies TEMPERATURE PROGRAMMED TECHNIQUES Temperature Programmed Reduction Sulfidation and Reaction Spectroscopy Thermal Desorption Spectroscopy PHOTOEMISSION AND AUGER SPECTROSCOPY X-Ray Photoelectron Spectroscopy Ultraviolet Photoelectron Spectroscopy Auger Electron Spectroscopy ION SPECTROSCOPIES Secondary Ion and Neutral Mass Spectrometry Rutherford Backscattering and Low Energy Ion Spectroscopy MOSSBAUER SPECTROSCOPY DIFFRACTION AND EXAFS X-Ray Diffraction Low Energy Electron Diffraction and Extended X-Ray Absorption Fine Structure MICROSCOPY AND RELATED TECHNIQUES Electron Microscopy Scanning Probe Microscopy Field Emission and Ion Microscopy VIBRATIONAL SPECTROSCOPIES Infrared, Raman and Electron Energy Loss Spectroscopy Case Studies in Catalyst Characterization