This article attempts to clarify how public performance affects General Budget Support (GBS) decisions in Tanzania and how performance indicators and GBS-driven incentives shape public policy design, budgeting, and performance. On the first issue, we find that development partners fail to agree on a common way to monitor performance, that headquarter policies rather than country performance is the main determinant of aid disbursements, and finally that the incentives General Budget Support creates are weakened by the lack of explicit rules regarding aid disbursements and the increasing number of donor-specific triggers. On the effects of General Budget Support performance monitoring on public policy decisions, we find that the lack of prioritization between donor triggers confuses the signal donors send to government, that the effect of the triggers are limited to the act of cutting or increasing aid, which stirs a lot of debate but not the intended development outcome, and finally that because of capacity constraints, government’s ability to affect outcomes cannot be taken for granted. Based on these findings we recommend a number of critical steps to enhance the effectiveness of GBS-driven incentives.