The United Nations aims to maintain international peace and security, while protecting human rights and upholding international law. However, United Nations whistleblowers over the years have revealed deep dysfunction within the organisation. This illuminating book combines first-hand accounts of these UN whistleblowers with academic reflections of their experiences. It argues that it is vital for International Organisations (IOs) such as the UN, which was created for the common good, to critically evaluate the mechanisms complicit in silencing these voices, ultimately undermining its purpose and creating unnecessary risk for the UN. The valuable lessons drawn from these transformative whistleblowing experiences and their analysis can be applied to all major organisations, especially to those operating under wider global and humanitarian governance structures.