Niklas Luhmann's systems theory is considered the most sophisticated and plausible theory of society. However, like its subject, it is complex and multifaceted. Christian Schuldt has taken on the challenge: he provides the reader with an understandable and even entertaining access to Luhmann's fascinating conceptual framework and skillfully conveys the theory that is "good for everything." Furthermore, he demonstrates that and how systems theory is particularly well-suited to describe and understand the interconnected society of the 21st century. In addition to presenting fundamental concepts such as self-reference, autopoiesis, communication, and observation, the book offers numerous examples of the practical applicability of systems-theoretical thinking.