Excerpts from The Power of Habit by Charles Duhigg

Take, for instance, studies from the past decade examining the impacts of exercise on daily routines. When people start habitually exercising, even as infrequently as once a week, they start changing other, unrelated patterns in their lives, often unknowingly. Typically, people who exercise start eating better and becoming more productive at work. They smoke less and show more patience with colleagues and family. They use their credit cards less frequently and say they feel less stressed. It's not completely clear why. But for may people, exercise is a keystone habit that triggers widespread change. "Exercise spills over," said James Prochaska, a University of Rhode Island researcher. "There's something about it that makes other good habits easier."

Studies have documented that families who habitually eat dinner together seem to raise children with better homework skills, higher grades, greater emotional control, and more confidence. Making your bed every morning is correlated with better productivity, a greater sense of well-being, and stronger skills at sticking with a budget. It's not that a family meal or a tidy bed causes better grades or less frivolous spending. But somehow those initial shifts start chain reactions that help other good habits take hold.

If you focus on changing or cultivating keystone habits, you can cause widespread shifts. However, identifying keystone habits is tricky. To find them, you have to know where to look. Detecting keystone habits means searching out certain characteristics. Keystone habits offer what is known within academic literature as "small wins." They help other habits flourish by creating new structures, and they establish new cultures where change becomes contagious.

Small wins are exactly what they sound like, and are part of how keystone habits create widespread changes. A huge body of research has shown that small wins have enormous power, an influence disproportionate to the accomplishments of the victories themselves. "Small wins are steady application of small advantage," one Cornell professor wrote in 1984. "Once a small win has been accomplished, forces are set in motion that favor another small win." Small wins fuel transformative changes by leveraging tiny advantages into patterns that convince people that bigger achievements are within reach.

"Small wins do not combine in a neat, linear, serial form, with each step being a demonstrable step closer to some predetermined goal," wrote Karl Weick, a prominent organizational psychologist. "More common is the circumstance where small wins are scattered. . . .like miniature experiments that test implicit theories about resistance and opportunity and uncover both resources and barriers that were invisible before the situation was stirred up."