Since its creation, the Kodokan has always emphasised randori training, prioritising the use of the nage waza and katame waza, reserving the atemi waza for study in the form of kata, in free practice and to develop self-defense sequences. As far as nage waza is concerned, the "nage no kata" is currently widely used as the main kata to learn the basics of projection techniques, where Tori performs the technique directly, without uke performing any action. The study of nage waza requires a deep and integral vision of the different concepts and principles that make it possible to effectively use the projection or throwing techniques including the counter techniques and in this context the master Kyuzo Mifune with the help of master Kazuo Ito developed in the 1940's the "nage waza ura no kata" or Kata of the projection counter techniques based to a large extent on the structure of the 15 techniques of the current nage no kata (with some changes). As has happened in the past, kata or methods that did not form an official part of the Kodokan tend to be forgotten or fall into disuse. The International Kano ryu school has been working hard for years to recover and "put into circulation" these interesting, effective and didactic methods. We have done so with the study of torite no kata, seiryoku zenyo kokumin taiiku, kime shiki (currently part of the former), joshi goshin ho, Mifune soen goshin jutsu, katame waza Ura no kata, etc, all of which have been published in various languages. Now it is the turn of nage waza ura no kata. We highly recommend the practice of this kata for the many benefits it brings, especially to randori and shiai lovers.