Habits involve a direct cue-behavior association in memory. When encountered, cues activate a single, specific well-learned behavioral response. Habits are acquired as a consequence of a history of cue-contingent behavioral repetition. Evidence shows that established habits are cue-contingent, share features of automaticity, and are goal- or reward-independent. Habit cues are readily detected in the environment, associated with short response latencies in computerized tasks and cause “action slips.” Habits are automatic in the sense that cues automatically activate habituated actions without reference to reflective processes. While habits may sometimes be acquired during deliberate goal pursuit, and continue to service goals, once established, cues will prompt behavior irrespective of current motivational state. Habit formation offers an important avenue for development of sustained behavior change interventions. Unlike motivational models of behavior change, habit formation has the potential to create sustained behavior change. Considerable progress has been made in delineating features of habit formation, particularly planning cue-action contingencies and ensuring repetition. Interventions that demonstrate the long-term superiority of habit interventions versus motivational interventions in promoting sustained behavior change require extended behavioral follow-up. Undesired habits share the same attributes as desired habits, so that undoing undesired habits represents a significant challenge for the science of behavior change.

Habitual behaviors are initiated automatically in response to situations in which they have been repeatedly performed in the past. Making a desired behavior habitual is thought to shield it against lapses due to low motivation, while disrupting habitual performance of undesired behaviors may aid cessation. This chapter outlines how developing new cue-behavior associations so that a habit can form may disrupt unwanted habitual actions. The strategies are suggested: avoiding cues, inhibiting responses to cues, or learning new habit associations to displace old ones. Forming a new habit requires sustained motivation and ability to initiate and maintain change as new associations form. Among those willing to change, behavior change techniques that promote action control (e.g., action planning, goal setting, using prompts and cues) may particularly facilitate habit formation. Purposeful habit disruption, requires motivation but is also facilitated by identifying triggers and either avoiding them or planning alternative responses. Habit change can be facilitated or obstructed by characteristics of the target behavior, situation, or actor. For example, behaviors that are easier to perform and driven by intrinsic motives rather than external pressure are likely to rapidly become habitual. Evaluations of habit interventions suggest that they are typically acceptable to recipients and show potential in achieving meaningful behavior change.