As a student of O Sensei from 1938 onward, Tohei Sensei discovered that before he could lead another’s mind he had to first control his own mind and body. Tohei Sensei was appointed as the chief instructor of O Sensei’s Aikido organization.  Over time, Tohei Sensei deepened his understanding of Aikido with mind and body coordinated and developed a method of communicating it to students. Through intensive and rigorous personal development and inquiry, he broadened and further developed his method of communicating and teaching Aikido. From 1953 to 1976, he had made over 18 trips to the West where he had spread Aikido and established Aikido dojos throughout the United States and over 20 foreign countries.

In 1971, he founded the Ki No Kenkyukai (Ki Society International) an organization where the principles of Ki and the coordination of mind and body were taught in detail.  In 1974, he established Shin Shin Toitsu Aikido, or Aikido with mind and body coordinated. Shin Shin Toitsu Aikido is often referred to Ki-Aikido, Aikido with an emphasis on Ki.