After a month of intensive political work at home and with allies abroad, the Biden administration may have assembled the right mix of sanctions and related policy tools to forestall Russian military action against Ukraine. The success of sanctions, according to our research, relies on four factors. First, sanctions must be multilateral in design, implementation, and enforcement. Second, in both their threat and multi-stage imposition, they must be clear, credible, and powerful. Third, all parties that threaten economic sanctions must be willing to incur costs. Finally, the sanctions must not simply be punitive but must be accompanied by diplomatic efforts to resolve the crisis.