From publisher blurb:
This add-on to any level-based game that incorporates skills and feats (like, for example, Pathfinder, D&D, or d20 Modern) provides a change of pace and feel to character advancement that is sure to please any player who has groaned at being just a few hundred XP short of the next level: The rules here give a simple mechanism for increasing skills and gaining feats between levels.
Designed by Steve Miller (formerly of Wizards of the Coast), these rules have been used in campaigns he's run for almost a decade.