The ‘development-security nexus’ marks a paradigm shift for development, security and humanitarian practice, with implications for education and development education. This article explores zigzag changes, initially towards human security and human development, then back towards donor governments’ own security and economic interests. Aid has become ‘bunkered’, while development’s scope has somewhat narrowed. The increasing salience of private actors and educational securitisation add to the ethical ambiguities and complexities. Four ethical dilemmas are explored: securitisation, privatisation / ‘NGOisation’, fragmentation, and declining internationalism. Development ethics considers both the ethical justifications for doing development and ethical judgments about development practices. Development ethics helps us think clearly about how responsibilities are assigned, ensuring that responsibilities are not assigned to the wrong actors. This article assesses a major new resource on development ethics (Drydyk and Keleher, 2018) and endorses the human development and capabilities approach (HDCA) as an ethical lens for assessing neoliberal securitisation.