Not all habits matter equally. Some are keystones: change one, and other changes cascade because the system reorganizes around a new standard.
This chapter follows a leader who focuses obsessively on one priority that seems narrow, almost boring. The point is not the topic itself, but the mechanism: a keystone habit creates small wins, new routines, and a shared narrative about what the group stands for.
Keystone habits also reshape identity. When a family starts eating together, other patterns shift. When a company commits to a clear habit, it changes what people notice, what they measure, and what they tolerate.
The chapter’s challenge is strategic. Instead of trying to fix everything, find the habit that forces the rest to move. One lever can move a room.