The term “groupthink” was coined in the early 1970s by psychologist Irving L. Janis. In 1972, Janis published his book Victims of Groupthink: A Psychological Study of Foreign-Policy Decisions and Fiascoes. Janis defines ”groupthink” as a “psychological drive for consensus at any cost that suppresses dissent and appraisal of alternatives in cohesive decision-making groups.” Janis identified eight symptoms of groupthink, including illusions of invulnerability, unquestioned beliefs, rationalizing, stereotyping, self-censorship, “mind guards,” illusions of unanimity, and direct to pressure. Janis blamed groupthink for several political “fiascos,” such as the Bay of Pigs invasion, the failure to prepare for the attack on Pearl Harbor, the escalation of the Vietnam War, and the Watergate coverup. Scholars have gone on to blame later events, including the decision to launch the doomed space shuttle Challenger, the Iran-Contra affair, and the Enron scandal on groupthink.

What is Groupthink?

Groupthink is a psychological phenomenon in which people strive for consensus within a group. Groupthink occurs when a group forms a quick opinion that matches the group consensus, rather than critically evaluating the information. Mass hysteria can be seen as an extreme example of groupthink. In many cases, people will set aside their own personal beliefs or adopt the opinion of the rest of the group. People who are opposed to the decisions or overriding opinions of the group as a whole frequently remain quiet, preferring to keep the peace rather than disrupt the uniformity of the crowd. The phenomenon can be problematic, but even well-intentioned people are prone to making irrational decisions in the face of overwhelming pressure from the group.

Groupthink seems to occur most often when a respected or persuasive leader is present, inspiring members to agree with his/her opinion. Groupthink is sometimes positive but is more often seen in a negative light, particularly in the U.S. and other countries that value individual opinion.

Groupthink is most often associated with business, politics, and policymaking, but it also relates to the psychology of collective phobias and mass hysteria. It’s believed that groupthink increases as group cohesiveness increases, which may help explain the psychological phenomenon of mass hysteria. Also known as epidemic hysteria, mass psychogenic illness, and mass sociogenic illness, mass hysteria is “a constellation of symptoms suggestive of organic illness, but without an identifiable cause, that occurs between two or more people who share beliefs related to those symptoms,” according to a 1997 review of research by The Johns Hopkins University School of Hygiene and Public Health. It is “seen as a social phenomenon involving otherwise healthy people.” Beyond causing mass hysteria, groupthink can discourage independent thinking in both school and the workplace.

Groupthink may not always be easy to discern, but there are some signs that it is present. There are also some situations where it may be more likely to occur. Janis identified a number of different “symptoms” that indicate groupthink.

  • Illusions of unanimity lead members to believe that everyone is in agreement and feels the same way. It is often much more difficult to speak out when it seems that everyone else in the group is on the same page.
  • Unquestioned beliefs lead members to ignore possible moral problems and not consider the consequences of individual and group actions.
  • Rationalizing prevents members from reconsidering their beliefs and causes them to ignore warning signs.
  • Stereotyping leads members of the in-group to ignore or even demonize out-group members who may oppose or challenge the group’s ideas. This causes members of the group to ignore important ideas or information.
  • Self-censorship causes people who might have doubts to hide their fears or misgivings. Rather than sharing what they know, people remain quiet and assume that the group must know best.
  • “Mindguards” act as self-appointed censors to hide problematic information from the group. Rather than sharing important information, they keep quiet or actively prevent sharing.
  • Illusions of invulnerability lead members of the group to be overly optimistic and engage in risk-taking. When no one speaks out or voices an alternative opinion, it causes people to believe that the group must be right.
  • Direct pressure to conform is often placed on members who pose questions, and those who question the group are often seen as disloyal or traitorous.

Why does groupthink occur?

Think about the last time you were part of a group, perhaps during a school project. Imagine that someone proposes an idea that you think is quite poor. However, everyone else in the group agrees with the person who suggested the idea, and the group seems set on pursuing that course of action. Do you voice your dissent or do you just go along with the majority opinion? In many cases, people end up engaging in groupthink when they fear that their objections might disrupt the harmony of the group or suspect that their ideas might cause other members to reject them.

A number of factors can influence this psychological phenomenon. Some causes:

  • Group identity: It tends to occur more in situations where group members are very similar to one another. When there is a strong group identity, members of the group tend to perceive their group as correct or superior while expressing disdain or disapproval toward people outside of the group.
  • Leader influences: Groupthink is also more likely to take place when a powerful and charismatic leader commands the group.
  • Low knowledge: When people lack personal knowledge of something or feel that other members of the group are more qualified, they are more likely to engage in groupthink.
  • Stress: Situations where the group is placed under extreme stress or where moral dilemmas exist also increase the occurrence of groupthink.

Groupthink can cause people to ignore important information and can ultimately lead to poor decisions. This can be damaging even in minor situations but can have much more dire consequences in certain settings. Medical, military, or political decisions, for example, can lead to unfortunate outcomes when they are impaired by the effects of groupthink.

Groupthink, The psychological phenomenon may have costs:

  • The suppression of individual opinions and creative thought can lead to inefficient problem-solving.
  • It can contribute to group members engaging in self-censorship. This tendency to seek consensus above all else also means that group members may not adequately assess the potential risks and benefits of a decision. 
  • Groupthink also tends to lead group members to perceive the group as inherently moral or right. Stereotyped beliefs about other groups can contribute to this biased sense of rightness.

It is important to note that while groupthink and conformity are similar and related concepts, there are important distinctions between the two. Groupthink involves the decision-making process.

On the other hand, conformity is a process in which people change their own actions so they can fit in with a specific group. Conformity can sometimes cause groupthink, but it is not always the motivating factor.

While groupthink can generate consensus, it is by definition a negative phenomenon that results in faulty or uninformed thinking and decision-making. Some of the problems it can cause include:

  • Blindness to potentially negative outcomes
  • Failure to listen to people with dissenting opinions
  • Lack of creativity
  • Lack of preparation to deal with negative outcomes
  • Ignoring important information
  • Inability to see other solutions
  • Not looking for things that might not yet be known to the group
  • Obedience to authority without question
  • Overconfidence in decisions
  • Resistance to new information or ideas

Group consensus can allow groups to make decisions, complete tasks, and finish projects quickly and efficiently—but even the most harmonious groups can benefit from some challenges. Finding ways to reduce groupthink can improve decision-making and assure amicable relationships within the group.

There are steps that groups can take to minimize this problem. First, leaders can give group members the opportunity to express their own ideas or argue against ideas that have already been proposed.

Breaking up members into smaller independent teams can also be helpful.

Ideas that might help prevent groupthink

  • Initially, the leader of the group should avoid stating their opinions or preferences when assigning tasks. Give people time to come up with their own ideas first.
  • Assign at least one individual to take the role of the “devil’s advocate.”
  • Discuss the group’s ideas with an outside member in order to get impartial opinions.
  • Encourage group members to remain critical. Do not discourage dissent or challenges to the prevailing opinion.
  • Before big decisions, leaders should hold a “second-chance” meeting where members have the opportunity to express any remaining doubts.
  • Reward creativity and give group members regular opportunities to share their ideas and thoughts.

When people in groups have diverse backgrounds and experiences, they are better able to bring different perspectives, information, and ideas to the table. This enhances decisions and makes it less likely that groups will fall into groupthink patterns.


This article is provided by Dr. Ralph Kueche (Child Psychologist). Dr. Kuechle is a Child and Adolescent Clinical Psychologist who specializes in treating children and their families who may be struggling with mood and behavioral issues. Learn more about Dr. Kuechle.