Origins of the theory
Lazarsfeld, Berelson and Gaudet (1944) conducted a panel study that repeatedly surveyed residents of Erie County, Ohio, during the 1940 U.S. presidential election. Expecting the mass media to change voters' decisions substantially, they found that few actually changed their minds and that people reported being more influenced by conversations with family, friends and coworkers than by the media. The researchers hypothesized that ideas often flow from radio and print to opinion leaders and from them to the less active sections of the population. This contrasted with the so-called magic bullet theory, in which media have direct and powerful effects on the public.
Opinion leaders and personal influence
Katz and Lazarsfeld (1955) surveyed women in Decatur, Illinois, about who influenced whom in shopping, fashion, public affairs and moviegoing. They reported that opinion leaders were not confined to an elite but were distributed across all strata of society, generally influencing people similar to themselves. Opinion leaders could differ by domain and tended to be more exposed to relevant media than others. Reviewing later research, Katz (1957) emphasized that opinions and behavior are formed and sustained within groups and interpersonal networks more than by the mass media. This view became central to the limited-effects paradigm, in which media effects are filtered and limited by interpersonal relations.
Critiques and extensions
Gitlin (1978) criticized the two-step flow theory and the limited-effects paradigm for measuring media influence narrowly as short-term attitude change, thereby missing the media's long-term, structural power to define which issues matter. Later research moved toward seeing the flow as multi-step rather than limited to two steps. Weimann (1982) reported that people at the margins of groups, rather than at the center, serve as bridges bringing in new information from outside. Using simulations, Watts and Dodds (2007) argued that networks of many easily influenced people may matter more for diffusion than a few influentials. Bennett and Manheim (2006) argued that personalized media produce a renewed one-step flow in which messages reach individuals directly, while Choi (2015) reported a two-step flow through opinion leaders in Twitter discussions. The theory is important, alongside diffusion of innovations and agenda-setting theory, for understanding the history of media effects research.
FAQ
- What is the two-step flow theory in simple terms?
- It is the idea that messages from news or advertising first reach opinion leaders who care about a topic, and then spread as those people talk to others. People are influenced more by those close to them than by the media.
- Does the two-step flow still apply in the social media era?
- Partly. Research finds that many people still get news through influential users on social media. But algorithms and personalized messages also deliver information directly to individuals, so many researchers describe the flow as having become one-step or multi-step and more complex.
Sources reviewed: 2026-10-26
References
- Lazarsfeld, P. F., Berelson, B., & Gaudet, H. (1944). The People's Choice: How the Voter Makes Up His Mind in a Presidential Campaign. New York: Duell, Sloan and Pearce. The 1940 election panel study where the hypothesis was born — read it to see the original evidence.
- Katz, E., & Lazarsfeld, P. F. (1955). Personal Influence: The Part Played by People in the Flow of Mass Communications. Glencoe, IL: Free Press. The Decatur study and the definitive treatment of opinion leaders — the theory's core text.
- Katz, E. (1957). The two-step flow of communication: An up-to-date report on an hypothesis. Public Opinion Quarterly, 21(1), 61–78. Katz's own update on a decade of research — a compact overview of the whole hypothesis.
- Gitlin, T. (1978). Media sociology: The dominant paradigm. Theory and Society, 6(2), 205–253. A sharp critique of the two-step/limited-effects paradigm — essential for its limitations.
- Weimann, G. (1982). On the importance of marginality: One more step into the two-step flow of communication. American Sociological Review, 47(6), 764–773. Shows marginal members bring information into groups — how the model grew into a multi-step flow.
- Bennett, W. L., & Manheim, J. B. (2006). The one-step flow of communication. The Annals of the American Academy of Political and Social Science, 608(1), 213–232. Argues targeted media brings back a one-step flow — good for rethinking the theory today.
- Watts, D. J., & Dodds, P. S. (2007). Influentials, networks, and public opinion formation. Journal of Consumer Research, 34(4), 441–458. Simulations questioning whether a few 'influentials' drive diffusion — a critical look at influencer assumptions.
- Choi, S. (2015). The two-step flow of communication in Twitter-based public forums. Social Science Computer Review, 33(6), 696–711. Tests opinion leadership in Twitter forums — does the two-step flow survive on social media?