Tim S. Grover is the preeminent authority on the science and art of achieving physical and mental dominance. Since 1989, he has been the CEO of Attack Athletics, travelling the world training, consulting, and speaking about the principles of athletic excellence, relentless drive, and mental toughness to athletes, coaches, and business leaders. He is the author of Relentless: From Good to Great to Unstoppable. He is based in Chicago.