Stalk training is the component of sniper school that hones a
sniper's stealthy approach. Snipers have to learn to move slowly,
patiently and methodically. If necessary, snipers will lie for days in
the same position to observe an objective or avoid detection. Army
Ranger Sniper describes the intricate process:
When you're stalking, you would be amazed when you're on the ground the things you walk over and don't look at. When you're trying to sneak up on somebody, even an anthill looks like a mountain. You have pick out your positions -- the next place you're going to crawl to. You ask yourself, "Is that going to cover me when I get there, and how am I going to get there?
To develop this ability, snipers have to pass perhaps one of the most challenging training games -- the stalk.
Stalk
training takes place in open grassy ranges. Students start at one end
of the range. One thousand meters down range, two instructors sit on top
of a truck or tower with spotter scopes. Sniper students must stalk
toward the instructors without being seen. To add to the challenge, the
instructors have two soldiers in the field called walkers. The instructors use radios to communicate with the walkers and try to find the sniper.

Of course, training exercises are different from deployment. Army Ranger Sniper explains it this way:
"In the real world, it's a lot easier to get up to an objective than you would think. When we did stalks, [the instructors] would have us get up to within 150 meters of the objective. In the real world, you would never get that close to an objective. The real world is actually a lot easier."Anywhere, any time, snipers are prepared to use their specialized skills to sneak into dangerous situations and disable an enemy force through a combination of close reconnaissance and deadly long-range fire.