Characters with this skill can hide in urban environments almost perfectly, using the shadows of doorways, back alleys, walls, and fences for cover. Hide tests should be made with a +20% modifier if the character is keeping still or a +5% modifier if the character is moving cautiously. Urban environments are basically built-up areas; the skill can be used both inside and outside of buildings. The distinction between urban and rural can blur in some circumstances, such as farm buildings, and in such cases the gamesmaster should decide the environment involved. These skills also apply to certain underground situations, such as artificial tunnels and rooms.
Obviously, there needs to be somewhere for the character to hide. The gamesmaster should ask the players to describe what their characters are doing to hide and modify the chances accordingly.