Modern research in transition metal chemistry relies extensively on the use of high-level electronic structure theory and advanced spectroscopic methods. The ability to leverage the combination of molecular theory and spectroscopy is essential for driving cutting-edge research in all fields of transition metal science, ranging from inorganic chemistry to biochemistry and from catalysis to energy research. The goal of this summer school is to provide young scientists with the fundamental knowledge and practical skills to incorporate this powerful combination in their own research.