Get people to make a small commitment now in order to get them to make a larger commitment later. That’s the idea behind the commitment theory presented in Influence: The Psychology of Persuasion by Robert B. Cialdini.

There is a need that we have as human beings to be consistent. Consistency is seen as a characteristic of a stable, well-rounded person. We strive, sometimes subconsciously, to be consistent with our beliefs and past actions.

When we make a commitment to something, especially a public commitment, we’re setting a standard for ourselves. Future decisions and actions will be weighed against that standard, and since we will most likely strive for consistency, we’ll choose to do something that supports that commitment rather than go against it.

But how does that apply to your marketing?

If you can get people to commit to a small purchase, or an action that is free but makes them take a stand in some way, you will set yourself up for future purchases.

A popular tool that many companies who rely on direct sales use is the “foot in the door approach”. Get a consumers to answer “yes” to a question, to sign a letter of intent, to request free information on a product, or to agree to a sales presentation, and they’ve already made a commitment. Later, when presented with an opportunity to confirm that commitment with a purchase, they have an internal conflict with saying “no”.

Does your company stand for something? Is there a cause you might be a leading voice for? Reach out to people asking them to sign a petition or call to action, knowing that if they do, you are getting a commitment from them that you can go back and use later on.

Another common example is companies who offer free giveaways as prizes for testimonial contests. Customers are asked to submit testimonials explaining why they like a certain product or brand, and winners are selected. But everyone who submits a testimonial is making a public commitment to that brand. Later, they will be inclined to act in a way that is consistent with that commitment, meaning buy more of that brand or product.

Share your ideas for how commitments can work for your company below. And check out Influence: The Psychology of Persuasion today.