This chapter provides a summary and critical account of the historical debates over the nature of information and knowledge, as background to the explanations based on support-bargaining and money-bargaining, and the use of the information interface, that are developed in following chapters. It provides also an account of the more recent treatment of information in the context of the neoclassical economic model. As intimated in the Introduction, the problems with information encountered in common economic transactions are difficult to reconcile with a mathematical model. The critique of the economics of information serves as an introduction to various aspects of money-bargaining. Support-bargaining and money-bargaining are closely interlinked, so that an account of one necessarily makes reference to the other.