Irving Janis was a 20th century social psychologist who identified the phenomenon of groupthink

Professional Life

Irving Janis was born in Buffalo, New York, in 1918. He studied at the University of Chicago and went on to receive his doctorate from Columbia University in 1948. He completed his postdoctoral study at the New York Psychoanalytic Institute. Between 1943 and 1945, Janis served in the Research Branch of the Army, studying the morale of military personnel. In 1947 he joined the faculty of Yale University and remained in the Psychology Department there until his retirement four decades later. He was also an adjunct professor of psychology at the University of California, Berkeley.

Janis focused much of his career on studying decision making, particularly in the area of challenging habitual acts such as smoking and dieting. He researched group dynamics, specializing in an area he termed “groupthink,” which describes how groups of people are able to reach a compromise or consensus through conformity, without thoroughly analyzing ideas or concepts. He revealed the relationship peer pressure has to conformity and how this dynamic limits the confines of the collective cognitive ability of the group, resulting in stagnant, unoriginal, and at times, damaging ideas.

Throughout his career, Janis authored a number of articles and governmental reports and several books including Groupthink: Psychological Studies of Policy Decisions and Fiascoes and Crucial Decisions: Leadership in Policy Making and Crisis Management. He worked with Carl Hovland to research theories of attitude and explore areas of psychology relating to persuasion. Janis was recognized for his many accomplishments over the years with awards such as the Socio-Psychological Prize from the American Association for the Advancement of Science in 1967, the Distinguished Scientific Contribution Award from the American Psychological Association in 1981, and the Society of Experimental Social Psychology’s Distinguished Scientist Award in 1991.

Janis and Marjorie Graham were married in 1939, and they raised two daughters. Janis died from lung cancer in 1990. 

Contribution to Psychology

Irving Janis developed the concept of groupthink to explain the disordered decision-making process that occurs in groups whose members work together over an extended period of time. His research into groupthink led to the wide acceptance of the power of peer pressure. According to Janis, there are several key elements to groupthink, including:

  • The group develops an illusion of invulnerability that causes them to be excessively optimistic about the potential outcomes of their actions.
  • Group members believe in the inherent accuracy of the group's beliefs or the inherent goodness of the group itself. Such an example can be seen when people make decisions based on patriotism. The group tends to develop negative or stereotyped views of people not in the group. 
  • The group exerts pressure on people who disagree with the group's decisions.
  • The group creates the illusion that everyone agrees with the group by censoring dissenting beliefs. Some members of the group take it upon themselves to become “mindguards” and correct dissenting beliefs. 

This process can cause a group to make risky or immoral decisions. However, in certain situations, groupthink can be an effective and productive means to an end, allowing groups to come to decisions in more efficient and expedited manners than if they remained engaged in discussion or disagreement. For example, a group planning a protest might more effectively stage the protest due to groupthink. Without groupthink, the group could get caught in endless arguments over strategy and beliefs. Groupthink has been explored in social contexts ranging from business and politics, to family and educational settings.


  1. Chapman, J. (2006). Anxiety and defective decision making: An elaboration of the groupthink model. Management Decision, 44(10), 1391-1404. doi:
  2. Irving L(ester) Janis. (2002). Contemporary Authors Online. Biography In Context. Retrieved from