The demand for various multimedia services over the Internet and Next Generation Networks (NGN) has been increasing rapidly and made feasible through the rapid advances in broadband networking technology. There are two main challenges for efficient multimedia content delivery in the NGN. First, there is a lack of mechanisms to support the delivery of multimedia content according to user context and preferences from multiple sources to a large number of end-users over various communication channels. Second, multimedia streaming in NGN is based on several signaling and transport protocols each of which has several functions and related methods - the challenge here is to determine the optimal blend of protocols and the specific methods to use for efficient multimedia delivery. This essentially means that the most efficient interaction models for multimedia content delivery are those that can effectively minimize use of network resources. This dissertation addresses both of these challenges. The book analyzes existing multimedia content delivery approaches in terms of efficiency and provides the design of reference architecture and a prototype implementation of the major components