In the book Willpower: Rediscovering the Greatest Human Strength, psychologist Roy F. Baumeister explores the links between self-control and success. His co-author, New York Times science columnist John Tierney tells Lynne Rossetto Kasper how we can structure our lives for both.

However you define success -- a happy family, good friends, a satisfying career, robust health, financial security, the freedom to pursue your passions -- it tends to be accompanied by a couple of qualities.