Book excerpt: The book deals with recent scientific highlights on molecular magnetism in Europe. Molecular magnetism is a new interdisciplinary discipline gathering together chemists and physicists, theoreticians and experimentalists. The book intends to provide the reader with documented answers to many current questions: How can chemists use soft conditions to transform molecules in light and transparent magnets. How does a molecular system can behave as a single molecule magnet. How to combine several functions in the same molecular system. How light can be used to switch molecular magnetic properties. How can molecules be used for ultimate high density information storage or in quantum computing. What kind of methods do physicists develop and use to explore these new properties of matter. What kind of concepts and calculations can be provided for theoreticians to design new objects and to better understand the field and to enlarge its exciting developments.