GraySpan Behaviors Preview

By the Stanford Behavior Wizard Team


An overview of GraySpan behaviors and techniques for achieving them.

GraySpan Behavior Overview

Gray Span BehaviorIf you want someone to reduce a behavior for a period of time, you are seeking a Gray Span Behavior.

Examples include:

  • Health: Eat fewer foods with corn syrup during 40-day program.
  • Environment: Drive a car less often this month.
  • Commerce: Spend less on lunch this week.

Gray Span Behaviors are common in interventions for health (“eat less”), environment (“consume less”), and personal financial security (“spend less”).

In a typical case, the behavior being reduced is not desirable. A reduction program for a fixed term (such as 14 days or a month) helps people see how a long term change might be possible. In other words, Gray Span can be a step to Gray Path (where the behavior reduction is meant to be permanent).

To achieve a Gray Span Behavior, all successful interventions work by altering at least one element from the Fogg Behavior Model:

  1. Remove the trigger that leads to the undesirable behavior
  2. Reduce ability to perform the behavior (make it harder to do)
  3. Replace motivation for doing the behavior with de-motivators:  pain, fear, or social rejection

Our Resource Guide for Gray Span Behaviors explains specific techniques and tools for achieving a reduction for a fixed term. It also highlights successful programs and online systems that exist for this purpose.

About Resource Guides

Our Stanford team created these Resources Guides to help people working on behavior change projects. We can make it easier for you to:

1. Learn about a specific type of behavior change

2. Create solutions for achieving that behavior

In the past, most designers and researchers guessed at solutions for changing behavior. And frankly most attempts failed. Today, rather than guessing at solutions, people who use our Resource Guides will have clear guidance.

Our Stanford team will continue to improve each of the 15 Resource Guides.  We welcome your input.

BJ Fogg, Ph.D. (
Director, Persuasive Tech Lab @ Stanford University



The Behavior Guides were created in 2010 and we are no longer updating or selling them.

There is still lots of useful information in these guides. If you’re interested in obtaining a specific guide, please email us ( and let us know in which guide you’re interested and why. We may be able to share a copy with you.

We hope you’ll also benefit from our more recent behavior design projects at:

–BJ Fogg, Ph.D. (
Director, Persuasive Tech Lab @ Stanford University


To view a sample guide, please fill out the form below.