Dan Heath's Upstream argues that we spend too much time reacting to problems and not enough preventing them. Heath, a business writer known for Made to Stick and Switch, examines why organizations default to downstream interventions (treating symptoms) rather than upstream ones (addressing root causes). He profiles schools that reduced dropout rates by identifying at-risk students early, police departments that reduced crime through community partnerships, and companies that solved customer problems before they escalated. Heath identifies barriers to upstream thinking, including a lack of ownership (no one feels responsible for prevention), tunnel vision (crisis mode crowds out long-term thinking), and difficulty measuring prevention (how do you count problems that didn't happen?). He offers frameworks for overcoming these barriers, illustrated with case studies across sectors. Upstream is practical and accessible, typical of Heath's collaborations with his brother Chip. The book has particular relevance for public health, where prevention is often underfunded relative to treatment. Heath writes for general readers and business audiences seeking actionable insights. Essential reading for anyone interested in organizational effectiveness, public policy, or thinking more systematically about solving problems before they occur.