Since the late 1980s, the exponential growth of the nonprofit sector, large amounts of funding devoted to it, occurrence of major scandals in the corporate and nonprofit realms, and fear that international non-governmental organizations (INGOs) are vulnerable to misuse of funds for terrorist purposes have contributed to creating a more demanding environment for INGOs through new calls for accountability from within and outside the sector. Many solutions proposed by INGOs and others seem to emanate from corporate sector practices. How well have norms of accountability traveled from the corporate to the nonprofit sector? Using interviews and archival data, I examine the cases of Greenpeace USA and Environmental Defense Fund (EDF) in order to examine the relationship between INGO adoption of corporate norms and INGOs financial performance. I argue that adopting corporate norms is likely to improve INGO financial performance. INGOs that copy corporate norms are likely to improve more financially than INGOs that adapt them because the former can respond more directly and rapidly to varied donor demands. However, INGOs which copy corporate norms are more likely to experience lower mission performance than INGOs which adapt them because copied corporate norms can conflict with the greater purpose of the organization or lead to goal displacement. If it is the case that INGOs which perform better financially are less likely to succeed in their mission, it could put into question the current collaborative relationships between INGOs and corporations as corporate norms may be incompatible, and even detrimental to INGOs purposes