For over 100 years baseball has been a popular sport in Japan. It has been the most popular since the founding of professional baseball in Japan. However, over the past 15 years many prominent Japanese players have left Nippon Professional Baseball (NPB) for Major League Baseball (MLB). While franchises in NPB would like to retain the services of their best players, the structure of the league as well as its finances and marketing operations have caused overall league revenues to stagnate despite the sport’s popularity. In addition to providing an overview and historical analysis of professional baseball in Japan, this paper examines the current issues specifically confronting NPB and its member clubs. Unless significant changes are made to enable NPB to compete in a globalized baseball economy, the league’s influence on professional baseball in Japan will wane.