The Saudi-led intervention in Yemen is a valuable case study in the coercive use of air power. Saudi Arabia’s bombing campaign demonstrates the danger of employing a punishment approach against a subnational actor in a multi-sided internal conflict. Strategies of collective punishment, blockade, and decapitation have all malfunctioned against a stubborn and resilient Houthi adversary. The early audit from Yemen endorses a denial strategy, supports the growing orthodoxy that air attack is most effectively applied in support of ground forces, and offers insight on the relative utility of interdiction and close air support for that purpose. The Saudi-led coalition’s performance also underscores how difficult it is to achieve positive objectives with proxy warfare, regardless of air support. This chapter dissects the campaign, assesses its effectiveness, and draws lessons about air power’s ability to influence the outcome of similar complex civil war scenarios elsewhere.