Previous research has found evidence that in high-profile cases, political action committees (PACs) sometimes punish members of Congress for voting in opposition to the PACs' interests. This finding contradicts the conventional understanding of campaign contributions as an inducement or reward for voting record or access to a member of Congress. To understand better the dimensions of the punishment strategy, we test whether corporate PACs engage in punishment by examining the pattern of contributions of finance and insurance PACs in the wake of the House vote on granting permanent normal trade relations (PNTR) with China in May 2000. Using ordinary least squares regression models, we find support for a punishment strategy of finance and insurance PACs as a result of a no vote on PNTR. The magnitude of the punishment is highest for those members of the House who have the strongest relationship with the PAC.Political scientists have been interested in political action committees (PACs) since their numbers began to grow in the 1970s. The behavior of PACs, however, is still not fully understood. We assume, for instance, that business PACs, because of their varied interests, follow "safe" strategies in deciding which campaigns to support. In other words, PACs will seek to develop long-term relationships with powerful members of Congress whose voting records support the interests of the PACs. Previous research on this topic has identified two main strategies followed by corporate PACs when making decisions on how to allocate their resources. First, PACs sometimes follow a strategy in which they seek access to legislators in return for campaign contribu-