This book provides an accessible introduction to systemic thinking and working based on recent system theory. It uniquely combines two perspectives and theoretical approaches in one work: the system theory of Paul Watzlawick and the sociological approach of Niklas Luhmann. The aim is to explain the fundamentals of systemic work in a clear and relatable manner for students, lecturers, and practitioners, with clear definitions and numerous examples from all areas of life. The book is suitable for deepening studies and for application in therapy, counseling, and social work. It particularly highlights the practical fields of family, living groups, and organizations. Readers of this book will be introduced to the thinking styles of the mentioned theories in an engaging way, enabling an independent and creative engagement with them.