The Galactic KND (Organization), or GKND for short, is supposedly an intergalactic organization of all children fighting a universal war against evil (teen-to-)adult tyranny.
Only one KND operative per planet may be chosen to join the ranks of the Galactic KND, a decision which is made through an elaborate and highly secretive process.
During the final season of Codename: Kids Next Door, Numbuh 1 is chosen to be Earth's Galactic KND operative. At the end of Operation: I.N.T.E.R.V.I.E.W.S., he passes his final test and confronts Numbuh 74.239, upon which the existence of the Galactic KND is revealed to him and the viewer. But in the end of the movie, it is seen that Numbuh 1 returns to Earth.