"Corporate groups are the preferred legal structure for enterprises since the 1920-1930s. Despite their omnipresence in most of our lives, very little is known about their structure and the means of how corporate control can be obtained and exercised. Infact, innovative means of control can be obtained and exercised in ways regulators have not thought of. This enables shadow business practices, understood as control-mechanisms that are not covered by regulation demanding transparency of corporate groups, such as non-equity modes of control including smart contracts on private blockchain platforms and other coordinative means of control. This recognition is of the essence for determination of reach and scope of for instance tort liability, tax, competition, labour law and more. It is argued in this book that finding a better framework for assessing the multifaceted corporate group of the 21st century necessitates, first, the disentanglement of the components of corporate groups and, second, the introduction of a new foundational framework to understand what constitutes a corporate group"--