In order to better understand the tax manipulation decision-making process—both legal uses of tax deductions and illegal tax evasion—this brief looks at the impact of gain/loss framing. Analysis of tax data confirms that tax decisions are influenced by “loss aversion.” For instance, taxpayers are more likely to pursue tax reduction activities when they make a loss smaller, as compared to when they make a gain larger. The brief looks at tools that policymakers have at their disposal for both deterring tax evasion and making exiting tax incentives maximally effective. The brief discusses instances when such gain/loss framing interventions might be deployed, and provides estimates around the size of the revenue responses they may generate. The author estimates that if tax filers who face losses experienced the lower motivation to manipulate shown by those facing gains, annual tax revenue would increase by $1.4 billion. Even attempts at marginal interventions, though smaller in predicted effects, might be financially worthwhile.