Simply giving employees a sense of agency- a feeling that they are in control, that they have genuine decision-making authority - can radically increase how much energy and focus they bring to their jobs.

The best agencies understood the importance of routines. The worst agencies were headed by people who never thought about it, and then wondered why no one followed their orders.

Self-discipline has a bigger effect on academic performance than does intellectual talent.

When a habit emerges, the brain stops fully participating in decision making. It stops working so hard, or diverts focus to other tasks. So unless you deliberately fight a habit -- unless you find new routines -- the pattern will unfold automatically.

The biggest moment of flexibility in our shopping habits is when we have a child, because when you think about it, all of your old routines sort of go out the window, and suddenly a marketer can come in and sell you new kinds of things.

However, to modify a habit, you must decide to change it. You must consiously accept the hard work of identifying the cues and rewards that drive the habits' routines, and find alternatives. You must know you have control and be self-conscious enough to use it -- and every chapter in this book is devoted to illustrating a different aspect of why that control is real.

As people strengthened their willpower muscles in one part of their lives—in the gym, or a money management program—that strength spilled over into what they ate or how hard they worked. Once willpower became stronger, it touched everything.