The document discusses several comprehensive models of customer relationship management (CRM). It describes four key models: 1) the IDIC model which focuses on identifying, differentiating, interacting with and customizing for customers, 2) Francis Buttle's 2004 model with a goal of enhanced customer profitability through various stages, 3) the QCi model which depicts activities to acquire and retain customers using people, processes and technology, and 4) Payne's five-process model separating CRM into strategic, operational and analytical processes. It also briefly outlines several additional CRM models and frameworks.