BJJ Move #15: North and South (position)

Here's a position you often get to when someone starts squirming around in your cross side.

WARNING! These techniques could result in serious injury or death if practiced incorrectly or even if performed correctly. They should only be practiced with the supervision of an experienced instructor.

North and South:
-position
-basic

With the legs tucked in, called "Kami Shiho Gatame;" with the legs out, "Kuzure Kami Shiho Gatame."
Basically, your opponent is on his back and you are chest-to-chest with him facing his feet. Hold onto his hips with your hands, pin his body / hips with your elbows, and stay heavy to control him.