How do adults learn? How well and effectively do they acquire knowledge? Horst Siebert explains the foundations of adult education in a comprehensible and scientifically substantiated manner. He combines renowned theories with new findings: from the history of research into learning and the brain, the concept of competence, group dynamics and coaching to the current trends in the development of theories. He also covers all important aspects of and approaches to lifelong learning. The publication offers orienting knowledge and a comprehensive overview of the current state of knowledge and research. It is aimed at students, teachers and educational staff.This 2nd edition includes a new chapter about the importance of humour when learning.