Introduction
1 History of the Concept
Kurt Lewins "Theory of Channels and Gate Keepers"，
David Manning White and "Mr. Gates"
Other Gatekeeping Models
Gatekeeping and the General Communication Process
2 The Gatekeeping Process
Antecedents of Gatekeeping
Social Roles of Gatekeeping
3 Theorizing About Gatekeeping
Individual Level
Communication Routines Level
Organizational Level
Extramedia， Social/Institutional Level
Social System Level
4 A New Gatekeeping Model
5 Future Research
References
Author Index
About the Author