Drawing on a wide body of research, including extensive in-depth interviews, THE ONE THING YOU NEED TO KNOW reveals the central insights that lie at the core of: Great Managing, Great Leadership and Great Careers. Buckingham uses a wealth of relevant examples to reveal that at the heart of each insight lies a controlling insight. Lose sight of this 'one thing' and all of your best efforts at managing, leading, or individual achievement will be diminished. For great managing, the controlling insight has less to do with fairness, or team building, or clear expectations (although all are important). Rather, the one thing great managers know is the need to discover and then capitalize on what is unique about each person. For leadership, the controlling insight is the opposite - discover and capitalize on what is universal to all your people, regardless of differences in personality, race, sex, or age. For sustained individual success, the controlling insight is the need to discover what you don't like doing, and know how and when to stop doing it. In every way a groundbreaking work, THE ONE THING YOU NEED TO KNOW offers crucial performance and career lessons for business people at every level.