Prior to our discovery of the stages of behavior change, most research and treatments for health risk behaviors, such as smoking, alcohol abuse, and unhealthy diets, were based on an action model. Behavior change was seen as an event when individuals stopped smoking, drinking, or unhealthy eating. Interviews with smokers who quit on their own taught us a new model: Behavior change is viewed as a process that unfolds over time and involves progress thorough six stages of change. The first stage we labeled Precontemplation, because at-risk individuals, such as smokers, are not intending to quit in the foreseeable future. They underestimate the pros or benefits of quitting and overestimate the cons or costs. They make up about 40 percent of smokers in the United States, and historically were excluded because the available science and practice did not know how to help them progress. We now know that across more than fifty risk behaviors progress from precontemplation to action, requires individuals to increase their awareness and appreciation of the multitude of pros of changing.

Once individuals progress to the Contemplation stage, they intend to take action in the next six months. But they have deep doubts about whether the efforts to change are worth it. Their pros and cons of changing are essentially equal. Their rule of thumb is, “When in doubt, don't act!” The second principle of progress is to lower the cons. If withdrawal from smoking is a big barrier, treatment can provide nicotine patches that can reduce this con.

Individuals who progress to the Preparation stage are ready to take action within the next month. They are convinced the pros outweigh the cons but are afraid that when they act, they may fail. They need to learn that just making the decision to act is not enough. They have to apply other principles, such as being prepared for their biggest risks for relapse. How will they cope with stress or distress? Who will they turn to for help and support, which is one of the best buffers for stress? What substitutes, such as chewing gum, or taking deep breaths to relax, will they use when tempted to smoke? These individuals are ready for action-oriented programs but make up only 20 percent of smokers.