Family businesses account for more than two-thirds of all companies in Germany. Despite their undeniable economic significance, the relevant academic disciplines such as business administration or sociology have so far not provided viable models for describing this unique coupling of family and business. Fritz B. Simon presents a comprehensible theory in this introduction for all those who are practically and scientifically involved with family businesses, whether as a family member, an employee of such a company, a consultant, or a researcher. Based on Luhmann's system and social theory and constructivism, family and business are described as social systems with their own communication and dynamics, the intersection of which in a family business presents the participants with a series of paradoxes.