Even when alcoholics’ brains were changed through surgery, it wasn’t enough. The old cues and cravings for rewards were still there, waiting to pounce. The alcoholics only permanently changed once they learned new routines that drew on the old triggers and provided a familiar relief.

O’Neill’s safety plan, in effect, was modeled on the habit loop. He identified a simple cue: an employee injury. He instituted an automatic routine: Any time someone was injured, the unit president had to report it to O’Neill within twenty-four hours and present a plan for making sure the injury never happened again. And there was a reward: The onl

The cue and reward become intertwined until a powerful sense of anticipation and craving emerges. Eventually, whether in a chilly MIT laboratory or your driveway, a habit is born.

This is the third aspect of how social habits drive movements: For an idea to grow beyond a community, it must become self-propelling. And the surest way to achieve that is to give people new habits that help them figure out where to go on their own.

“All our life, so far as it has definite form, is but a mass of habits,” William James wrote in 1892.

This process within our brains is a three-step loop. First, there is a cue, a trigger that tells your brain to go into automatic mode and which habit to use. Then there is the routine, which can be physical or mental or emotional. Finally, there is a reward, which helps your brain figure out if this particular loop is worth remembering for the futu

The habits that matter most are the ones that, when they start to shift, dislodge and remake other patterns.

By focusing on one pattern—what is known as a “keystone habit”—Lisa had taught herself how to reprogram the other routines in her life, as well.

But countless studies have shown that a cue and a reward, on their own, aren’t enough for a new habit to last. Only when your brain starts expecting the reward—craving the endorphins or sense of accomplishment—will it become automatic to lace up your jogging shoes each morning.