The passive traits in The Gambler and Quiet Knife trait trees each increase your stealth movement speed by 40% and the latter also increases your stealth level by 2, making you harder to detect.
The traits Leaf Walker and Footpad in the Gambler and Quiet Knife trait trees each increase your stealth level by up to 5.
The trait Strike from Shadows in the Quiet Knife trait tree increases your critical chance from stealth by 5% and at max rank your critical damage from stealth by 20%.
The trait Hidden Dagger in the Quiet Knife trait tree increases your damage from stealth by up to 25%.
The trait Sneak Attack in the Quiet Knife trait tree increases your damage from stealth by 100%.
The set bonus Improved Sneak in the Quiet Knife trait tree makes your Surprise Strike and Cunning Attack skills guaranteed critical hits when used from stealth.
Sneaking is a very useful ability for Burglars. You don't need to clear a full camp with Orcs to get to your destination, just be careful and sneak around. Attacking from stealth increases your damage, especially if you are in red line.
While sneaking or in stealth, the following skills become usable: