Charles Duhigg\'s examination of what propels our unconscious daily choices may not be the self-help book some readers might have wished for, but that shouldn\'t detract from its achievement as a compelling guide to habit. The Power of Habit explores the world of marketing through the lens of retail chains. It does so by examining the patterns evident in shopping trends. And though it is decidedly populist in its approach, reducing these behavioural transactions to simple formulas - a craving requires a habit to sate it, he contends - each chapter does at least manage to shed some light on why consumers act in the way they do. For the more sceptical reader, Duhigg\'s continuous emphasis on habit as the sole driver of decision-making, good or bad, might prove unnecessarily repetitive. Add to that the often faux-scientific construct of his discussions and this does not always feel like a solid or particularly rich survey. That said, the accessibility of Duhigg\'s writing manages to elevate The Power of Habit to something that is decidedly above average. By / The National