Philanthropy has long been a cornerstone of financial sustainability for cultural institutions, enabling them to preserve heritage, engage communities, and innovate programmes. However, recent controversies, such as the backlash against the Sackler family’s donations due to their ties to the opioid crisis, have brought heightened scrutiny to donor relationships. This chapter explores the complex ethical dilemmas faced by cultural institutions as they navigate the intersection of financial necessity and public accountability. Using the National Portrait Gallery in London and its 2019 decision to decline a significant donation from the Sackler Trust as a case study, this chapter examines the pressures institutions face in balancing ethical considerations with the imperative to secure funding. Key themes include the growing influence of activist movements, the role of transparency in maintaining public trust, and the need for robust ethical frameworks to guide donor evaluations. The analysis highlights the challenges posed by controversial funding sources, emphasising the delicate balance between reputation management and financial sustainability.