Book excerpt: This book examines labour regulation and labour mobility in two professional baseball leagues: Major League Baseball in the United States and Nippon Professional Baseball in Japan. Through vivid comparative study, Matt Nichol explores how each league internally regulates labour mobility and how this internal regulation engages with external regulation from the legislature, statutory authorities and the courts. This comparison of two highly restrictive labour markets utilizes regulatory theory and labour regulation and suggests a framework for a global player transfer system in baseball.