Are Goodwill Ambassadors Good for Business?\\The Impact of Celebrities on IO Fundraising

International organizations (IOs) increasingly raise funds from individual donors, including almost a billion USD for UNICEF in 2017, but very little is known about the factors these donors respond to or how IOs attract them. Individual contributions can be a significant source of IO autonomy, so strategies employed by IOs to enhance them are important to understand. We conduct a survey experiment to analyze the effectiveness of a commonly used IO fundraising method: celebrity Goodwill Ambassadors. We find that celebrity endorsement is only an effective fundraising tool under certain conditions. Specifically, we find no unconditional ATE, but do find that men's tendency to donate less than women is mitigated when a Goodwill Ambassador endorses a UNICEF cause, and that donors who share an ethnicity with the endorser donate more. These findings highlight the need to appropriately target Goodwill Ambassador campaigns but that, when effective, they can bring substantial additional funding.