Sneak

Sneak is a Fallout, Fallout 2, and Fallout Tactics skill.

Quiet movement, and the ability to remain unnoticed. If successful, you will be much harder to locate. You cannot run and sneak at the same time unless you have the Silent Running perk. Initial Level: Starting Sneak skill is equal to 25% + (1% x Agility). Average characters will have a 30% Sneak.