The basic role-playing approach in Rules of Thumb is to resolve all situations through collaborative narration. If this becomes impossible or undesirable, the Narrator (Game Master) will call for a Task Resolution. The Narrator determines a Base Difficulty, applicable modifiers are applied, and the player rolls (usually) 2d10 and compares the result. The rules provide substitute statistics if other dice types are desired ("if players prefer other types of dice").
Characters have Traits and Attributes, but generally character creation is free-form with narrative tags providing characterization and capability. Combat is slightly more detailed in terms of difficulties.
The system as presented is utilized with a post-apocalyptic setting. However, the rules would be usable with any traditional genre.