Recent remarkable changes in computing and communication environment including increases in the number of machines per person and easy access to interconnection networks have encouraged people to retrieve information with whatever they have (machines), wherever they are (network availability). For information retrieval applications that often serve a fairly large client population, push-based data dissemination is preferable, with which data items are delivered to clients via broadcast without explicit data requests from the clients. This book explains why push-based dissemination is attractive, lists what type of methods should be developed to facilitate it, and illustrates where the performance (e.g., response time, energy efficiency) tuning can be done. In terms of network types, not only a closed network case like satellite networks but also an open network case like wireless sensor networks are considered. This book should be useful to professionals in computer communications, or anyone else who may be considering next-generation business powered by various types of wireless networks from television broadcast networks to wireless ad hoc sensor networks.