The concept of intermediation has existed for a long time and taken numerous different forms. In this introductory chapter, we will therefore start by examining the state of the art of intermediaries through a range of different disciplines (history, management, economics, health, sociology), highlighting their historical evolution and current forms. We will then present the different models and theories of intermediation and their development, to produce an appreciation of their similarities and differences and a comprehensive view of the subject. This will allow us, in the last section, to propose the framework for a general theory of intermediation, in terms of organisational architecture and the services provided.
Correction to: Dedicated breast CT: state of the art—Part I. Historical evolution and technical aspects
