At IFW Dresden the materials for electrochromic devices can be characterized. Hence, the influencing factors of the charged species, which determine the color of the devices, can be defined. With our long-standing expertise and comprehensive analysis of a variety of spectroscopic methods, which are combined with electrochemistry, changes in structure, properties and stability can be followed in situ. Only materials of purely organic compounds, organometallic complexes or electroactive polymers can be analyzed by the described methods.