The vertical shield is the most important one to master out of all the variations of the shielding theme. The concept is to create a barrier or obstruction that be used to stop or deflect an imcoming attack without exposing your vital targets. The shield is not a passive technique in which you let your opponent beat on for any more length of time then is needed to escape. Instead, you must use it to hide behind and counter attack from it aggressivley and stratgeically. When performing the shield the trick is to stay tight and compact, and not reachout to block while keeping your limbs close to your head area with you eyes open and head tucked down.  You also must keep your vision and perception at all times through the entire shielding process. Furthermore, you cannot become passive while shielding, you should be looking for the pauses or openings in your opponents combat,, or actions so you can counter attack ASAP. Remeber the shield in not a perfect defense, and no defense in it of itself is perfect. However, the shield is a concept that can buy yourself more protection then other forms of defense against worse case scenarios if you use it correctly. This is where operator error applies.