So often in life, we get stuck in a cycle of response. We put out fires. We deal with emergencies. We stay downstream, handling one problem after another, but we never make our way upstream to fix the systems that caused the problems. Cops chase robbers, doctors treat patients with chronic illnesses, and call-center reps address customer complaints. But many crimes, chronic illnesses, and customer complaints are preventable. So why do our efforts skew so heavily toward reaction rather than prevention? probes the psychological forces that push us downstream—including “problem blindness,” which can leave us oblivious to serious problems in our midst. And Heath introduces us to the thinkers who have overcome these obstacles and scored massive victories by switching to an upstream mindset. One online travel website prevented twenty million customer service calls every year by making some simple tweaks to its booking system. A major urban school district cut its dropout rate in half after it figured out that it could predict which students would drop out—as early as the ninth grade. A European nation almost eliminated teenage alcohol and drug abuse by deliberately changing the nation’s culture. And one EMS system accelerated the emergency-response time of its ambulances by using data to predict where 911 calls would emerge—and forward-deploying its ambulances to stand by in those areas. delivers practical solutions for preventing problems rather than reacting to them. How many problems in our lives and in society are we tolerating simply because we’ve forgotten that we can fix them?