Koei-Kan Karate-Do is a traditional system of martial art, originating in Japan. Master Eizo Onishi founded it in 1952. His teacher, Master Kanken Toyama, suggested the name "Koei-Kan" to Onishi. The basic translation of Koei-Kan, happiness (ko), prosperity (ei), and hall or house (kan), implies its underlying philosophy: "prosper with happiness toward the future." The ultimate purpose of Koei-Kan, by means of combative training and discipline, is to cultivate character. Koei-Kan is devoted to developing the spirit, and encourages the individual to find success and fulfillment.

A traditional martial art such as Koei-Kan is distinguished from other disciplines in many respects. Primary among these is its reliance upon ancient and authentic teaching methods, developed and perfected over generations. The physical discipline, the art of karate-do, also retains an underlying philosophy, which can be characterized in a few ideas. A true martial art is foremost a defensive discipline: "karate ni sente nashi" (in karate there is no first attack). The ultimate target of the combat is an interior one, seeking after the ultimate goal of mushin, no-mindedness, a flowing, open state of mind. Thus one holds no preconceptions, and acts spontaneously, both during combat and ultimately in life as a whole. This is exemplified in the meaning of the term "karate", empty (kara) - hand (te), which not only signifies a hand free of weapons but also a mind free of distraction.

The means of instruction in Koei-Kan are also traditional. All students start from the beginning. The practice and application of karate is built on a foundation of fundamentals. Instruction encompasses a wide range of fighting skills built upon this foundation, honed through continual repetition and practice. Japanese terminology is employed, and students are expected to pay heed to proper form and etiquette. Students are also required to retain a basic knowledge of the history of karate as well as the origins of Koei-Kan.

While traditional in its methods, Koei-Kan Karate-Do is nonetheless a versatile and effective fighting discipline. Course instruction, conducted and supervised by yudansha (black-belts), begins at the white-belt level up through the black-belt ranks. The Koei-Kan curriculum is broad and varied. Central is the necessity of proper conditioning. Conditioning class develops strength and endurance, as students repeatedly execute basic techniques and combinations. Conditioning and proper execution are further developed through the practice of kata, the traditional forms signifying an imaginary battle. Practicing kata is a basic principle of Koei-Kan, as it connects the system to its roots in Okinawa and Japan, and unfies the many Koei-Kan dojo throughout the system. Finally, students further develop their skills by means of kumite, contact sparring of various sorts that permits direct application of fighting methods. The entire course-study of Koei-Kan Karate-Do encompasses the following:

• Kihon Waza: "basic technique", developing proper form through practicing punches, strikes, kicks, and blocks
• Kata: traditional combat "forms", a foundational principle of Koei-Kan, essential in developing strong technique
• Kumite: contact sparring, from controlled one-step to bogu (armored full-contact)
• Tenshin Waza: body-transfer technique, a system of evasive and attack methods
• Nage: sweeps and throws
• Gyaku-Te: "reverse-joint", a system of submission and control holds
• Kobudo: weapons training

Rank advancement is based on merit. Testing students are expected to execute proper form, as well as understanding basic terminology and principles appropriate to their rank. Koei-Kan's belt-ranking system comprises an intermediate-beginner's belt (shichi-kyu), then three levels of green-belt, three levels of brown-belt, until one achieves black-belt.

A dedicated student can earn a black belt within about five years.