"The earlier, the better": Early intervention is now more than just a buzzword; it is established in many places. Initiated with enthusiasm in the 1960s, the initial expectations of success have been tempered by a realistic view of the achievable therapeutic effects in practice, and the concepts have evolved. This prompted a critical summary of the theory and practice of early intervention and highlighted perspectives for future work. More than 1,000 participants gathered for a congress on this topic. Over 50 renowned scientists and practitioners from relevant disciplines presented on the fundamentals, current state of knowledge, and methods of early intervention. However, this publication is much more than just a collection of presentations: the editors have succeeded in providing current information through careful structuring and editorial revision.