Cialdini Principles of Persuasion Glossary

Welcome to the annotated glossary of the key terms of Robert Cialdini’s influence principles.

This glossary is tailored for sustainability professionals in any sector.

Influence is at the heart of all sustainability work. Whether you’re working on energy efficiency, water conservation, the circular economy, sustainable transportation or ESG initiatives, success depends on more than technical expertise – it requires being able to persuade ethically and effectively.

This glossary is your quick reference guide to the language of influence and persuasion. These terms will help you navigate conversations, craft messaging and identify opportunities to build cooperation and drive action – whether you’re working with internal teams, leadership, stakeholders or customers.

Why the Robert Cialdini Principles of Persuasion Matter

Sustainability success often hinges on behaviour change – convincing executives to fund projects, motivating customers to adopt new programs, aligning stakeholders around climate goals and more – and on achieving professional and personal objectives through effective influence.

Generally speaking, persuasion and influence play a crucial role in shaping workplace behaviors and advancing sustainability initiatives.

This glossary gives you the key vocabulary and concepts that make those strategies work, as well as the efforts required to influence and persuade others.

Understanding the principles of persuasion gives practitioners an advantage in driving change and reaching sustainability goals.

How to Use This Influence Glossary

If you received this glossary as part of your Robert Cialdini Ethical Influence Practitioner certification, you’ll notice that each term has a reference such as:

“Refer to the following module of the training to learn more: Module X.”

These references point to the specific module where the concept is introduced or taught in depth. For example, if you see Module 4, that corresponds to the section on Reciprocity, including examples, activators and amplifiers.

What You’ll Find in the Glossary

• Core Terms: Definitions of the seven principles of persuasion (Reciprocity, Liking, Social Proof, Authority, Unity, Consistency, Scarcity).

• Key Concepts: Supporting ideas like “activators,” “amplifiers,” and “contrast,” explained in context.

While Cialdini's principles are foundational to understanding persuasion, alternative models and recent behavioral science research also inform modern approaches, emphasizing communication, collaboration, and social capital.

This glossary is your quick reference to keep influence top of mind as you plan strategies, draft communications, choose the right words to maximize persuasive impact, and engage stakeholders.

Annotated Glossary of Key Influence and Persuasion Terms for Sustainability Practitioners

• Activator: An activator is an event or action that causes an influence principle to begin operating. It is like turning on a light switch to engage the power of a principle. Each principle has triggers that activate its power, which sleuths aim to identify and utilize. Specific behaviors, such as making a request or offering a compliment, can serve as activators for the principles of persuasion.

  • Refer to the following module of the training to learn more: Module 4

• Amplifier: Any event or action that increases the effectiveness or power of an influence principle. It is like turning up a dial to increase the strength of a principle. The Contrast phenomenon amplifies every principle of persuasion. Surprising gestures, such as unexpected gifts or thoughtful actions, can also amplify the effect of a principle. Willingness to pay can be influenced by perceived value, familiarity, or reciprocal generosity, making amplifiers important in motivating action.

  • Refer to the following module of the training to learn more: Module 4

• Authority (Principle): States that people, especially when unsure, rely on those with superior knowledge or experience for guidance on how to behave. It stems from expertise rather than hierarchical power. For example, a faculty member is often seen as a knowledgeable expert whose guidance is trusted. This principle, along with social proof, is used to reduce uncertainty within the Core Motives Model. Authority is a powerful principle in negotiation and influence, as it can significantly shape outcomes by fostering trust and compliance.

  • Refer to the following module of the training to learn more: Module 8

• Bungler: A type of influence practitioner who either doesn’t know the influence principles or doesn’t understand how to use them effectively, thus fumbling away influence opportunities that are readily available. An example is a software company owner who inadvertently dismissed a customer’s gratitude, costing him future business.

  • Refer to the following module of the training to learn more: Module 2

• Commitment: A prior statement, choice, or action made by an individual, which creates a strong internal and interpersonal pressure to act consistently in the future. Once people have made a choice, taken a stand, or adopted a position, they feel a tremendous drive to be consistent.

  • Refer to the following module of the training to learn more: Module 9

• Consistency (Principle): States that people feel a need to be consistent with their prior commitments (statements, positions, actions). It is activated by reminding people of these existing commitments. This principle, along with scarcity, is used to motivate action within the Core Motives Model. Its impact is amplified when commitments are made actively, publicly, and voluntarily. Reducing the effort required to act consistently increases compliance. The sixth principle is a key influence strategy, highlighting the importance of appealing to emotions and motivation, not just logic.

  • Refer to the following module of the training to learn more: Module 9

• Contrast Phenomenon: Allows persuaders to change the way people experience anything by shaping what they experience first. Two different things will be perceived as even more different if they are presented one right after the other. It is crucial to set the context before making a request, and sleuths lead with the biggest and best comparison, answering the question “compared to what.” For example, when someone faces a long wait time after seeing a shorter one, they may attribute their situation to bad luck, illustrating how perception is influenced by comparison. People are more likely to be persuaded when principles like reciprocity, liking, authority, and social proof are used.

  • Refer to the following module of the training to learn more: Module 3

• Cooperation: Working with someone toward a common goal; one of the activators of the Liking principle. Shared interests and mutual goals promote cooperation, which in turn promotes liking. Skilled negotiators, for example, spend significant time searching for complementary interests and goals. Employing these principles leads to more successful negotiation or influence outcomes, as supported by research.

  • Refer to the following module of the training to learn more: Module 5

• Co-creation: A process where people work together to accomplish a task or create something jointly, fostering a greater sense of “we-ness” and unity. Inviting customers to co-create products or services by requesting their advice (rather than opinions) leads to greater favorability and brand loyalty.

  • Refer to the following module of the training to learn more: Module 6

• Core Motives Model (of Social Influence): Developed by Dr. Gregory Neidert, this model helps individuals understand how and when to most effectively employ the Principles of Influence for maximum impact, by prioritizing principles based on the persuader’s main goal: cultivating relationships (Reciprocity, Liking, Unity), reducing uncertainty (Social Proof, Authority), or motivating action (Consistency, Scarcity). The model builds on Cialdini’s principles and incorporates new insights from behavioral science research to adapt to modern influence challenges.

  • Refer to the following module of the training to learn more: Module 2

• Credibility: A crucial component of the Authority principle, comprising two parts: perceived expertise and perceived trustworthiness. Research shows that a credible communicator is the single most powerful authority communicator.

  • Refer to the following module of the training to learn more: Module 8

• Decision Triggers: Single, reliable pieces of information that generally guide people in making their decisions, especially in complex or overwhelming environments. The seven principles of influence serve as these triggers, offering simplifying ways to choose and prompting automatic tendencies to decide. People are more likely to be persuaded when these principles are strategically applied.

  • Refer to the following module of the training to learn more: Module 1

• Entitlements: Perks or amenities that people come to expect as part of a situation, rather than viewing them as special gifts. They are seen as ordinary and do not trigger the principle of reciprocity effectively. An example is free water that is always available.

  • Refer to the following module of the training to learn more: Module 4

• Exclusive Information: Information that is scarce because not everyone has access to it; a powerful amplifier of the Scarcity principle. It is most powerful when new or fresh (like “bread,” not “wine”), and sharing it quickly is crucial.

  • Refer to the following module of the training to learn more: Module 10

• Expertise: A component of credibility under the Authority principle, referring to an individual’s true knowledge, experience, and credentials relevant to a topic. It is best conveyed by others introducing you or by sending written evidence of your background ahead of a meeting, rather than through self-promotion.

  • Refer to the following module of the training to learn more: Module 8

• Influence Process: A four-step process (Step Back, Think, Solicit Input, Create a Plan) designed to generate more effective and ethical outcomes when applying the principles of influence, especially in group settings. This process helps clearly define the challenge, privately identify influence opportunities, gather ideas efficiently, and create actionable plans. Multiple attempts may be needed to influence others, and some attempts may fail, but learning from these experiences is key to improvement. Consistent efforts are essential in developing influence skills. Applying these principles increases the likelihood of successful influence and negotiation outcomes.

  • Refer to the following module of the training to learn more: Module 2

• Kinship: Cues of familial or tribal oneness; an activator of the Unity principle. It can include actual blood, marriage, or adoption ties, or be elevated by increasing the frequency of positive interaction with relationship partners, fostering a sense of “we-ness.”

  • Refer to the following module of the training to learn more: Module 6

• Liking (Principle): States that people say yes to those they know and like. It is activated by similarity, praise, and cooperation. This principle, along with reciprocity and unity, is used for cultivating relationships within the Core Motives Model. Even small commonalities or sincere compliments can significantly build rapport. 

  • Refer to the following module of the training to learn more: Module 5

• Localism: A form of unity activated by shared locality; people feel a sense of "we-ness" with those who share their living space, neighborhood, or community. This powerful unifying force, even when subtle, can dramatically influence decisions, as seen in political campaigns or even life-saving situations. 

  • Refer to the following module of the training to learn more: Module 6

• Loss Aversion: The finding that people are more influenced to act by the prospect of losing an item of value than by the prospect of gaining that very same thing; a central concept in the Scarcity principle. This innate fear of missing out (FOMO) is a powerful driver of behavior. 

  • Refer to the following module of the training to learn more: Module 10

• Loss Framing: Communicating reasons for an offer primarily in terms of the benefits and advantages that will be missed or foregone if prospects don't choose a particular direction; an amplifier of the Scarcity principle. This resonates more forcefully with people than merely emphasizing what can be gained. 

  • Refer to the following module of the training to learn more: Module 10

• Moment of Power: The crucial time immediately after an initial offer is rejected, during which a well-prepared fallback offer (concession) can be presented to trigger reciprocal concessions. Delaying this offer diminishes its perception as a concession, making it seem like just another proposal. 

  • Refer to the following module of the training to learn more: Module 4

• Praise: Compliments or positive statements given to others; an activator of the Liking principle. It is most effective when sincere, given behind a person's back, or when it reinforces a desired trait, as this is perceived as more genuine and can lead to the complimenter liking the recipient more. 

  • Refer to the following module of the training to learn more: Module 5

• Reciprocity (Principle): States that people feel obligated to return favors, gifts, or acts of kindness. Doing a small favor for someone can create a social obligation, increasing the likelihood of reciprocal action in the future. This principle is a powerful motivator in both social and professional contexts. Additionally, willingness to pay or contribute can rise when individuals perceive value, familiarity, or reciprocal generosity.

  • Refer to the following module of the training to learn more: Module 4

• Reward: Something given only after a person does something, making it conditional. Often less effective than gifts in triggering reciprocity because rewards can suggest a lower level of trust or appear as bribes, whereas gifts are unconditional and initiate an exchange. 

  • Refer to the following module of the training to learn more: Module 4

• Scarcity (Principle): States that people assign more value to opportunities, products, or information that are less available. Scarcity motivates action by creating a sense of urgency and exclusivity. Persuading others is more effective when you highlight what is unique or socially validated, making the opportunity feel rare and desirable.

  • Refer to the following module of the training to learn more: Module 10

• Sleuth: A type of influence practitioner who knows the influence principles, knows how to use them, and knows how to use them ethically, using only honest information so that everyone wins. Sleuths do not manipulate but inform others into "YES" so they make wise choices, always doing their homework to uncover genuine opportunities for influence. 

  • Refer to the following module of the training to learn more: Module 2

• Smuggler: A type of influence practitioner who knows the influence principles but chooses to use them illicitly or dishonestly, fabricating facts or counterfeiting the principles with the goal of winning at any cost. This approach leads to dishonest gains that ultimately become losses, damaging long-term credibility. 

  • Refer to the following module of the training to learn more: Module 2

• Social Proof (Principle): States that people look to others’ actions and behaviors to determine what is correct, especially in uncertain situations. Perceptions of reality are shaped by what is common or accepted in a group, which can differ from actual behavior or beliefs. Persuading others is often easier when you can show that a choice is socially validated by others.

  • Refer to the following module of the training to learn more: Module 7

• Synchronizing: Acting together with others in coordinated ways; an activator of the Unity principle that can elevate feelings of unity and cooperation. It includes collective work and joint creation, fostering a stronger sense of "we-ness." 

  • Refer to the following module of the training to learn more: Module 6

• Trappings of Authority: Observable cues that typically communicate someone's authority status, such as high-end clothing, confident speech, or professional titles. These are most potent when making a first impression, as people often react automatically to them without deep thought. 

  • Refer to the following module of the training to learn more: Module 8

• Trustworthiness: A component of credibility under the Authority principle, referring to being perceived as offering expert information in an honest, unbiased fashion. It can be established by being an "always-on" source of information or, for immediate impact, by acknowledging a minor drawback early in a message before presenting strengths. 

  • Refer to the following module of the training to learn more: Module 8

Social Influence: The Hidden Force Shaping Human Behavior

Social influence is one of the most powerful forces shaping human behavior, often operating beneath the surface of our everyday decisions. At its core, social influence refers to the ways in which people’s thoughts, feelings, and behaviors are affected by the presence or actions of others—whether those others are physically present, imagined, or simply implied. In the world of psychology and sales, understanding social influence is essential for anyone who wants to guide human behavior and achieve meaningful results.

Key principles of influence—such as reciprocity, scarcity, authority, consistency, social proof, liking, and unity—are the building blocks of social influence. These principles help explain why people tend to follow the lead of knowledgeable experts, respond to genuine compliments, or act quickly when faced with a limited-time offer. For example, in sales, highlighting how many others have chosen a product (social proof) or emphasizing a product’s limited availability (scarcity) can significantly increase the likelihood of a purchase. In psychology, these same principles help us understand why people conform to group norms or seek approval from those around them.

The impact of social influence extends far beyond simple transactions. It shapes our feelings, guides our behaviors, decision making, and even affects our sense of self. Most people are influenced by the behaviors and opinions of others, especially in situations where the right course of action is unclear. This is why understanding the science behind social influence is so valuable: it allows us to identify the key factors that drive human behavior and to use these insights in an ethical manner.

By mastering the principles of social influence, you gain the ability to persuade and motivate others more effectively—whether you’re leading a team, building relationships, or driving change in your organization. Ultimately, understanding how social influence works is not just about achieving success; it’s about helping people make better decisions and creating positive outcomes for everyone involved.