This book provides a comprehensive description of the United Nations procurement rules. Benefiting from the author’s extensive legal experience from the secretariats of the United Nations and UNIDO, the work offers a comparison with the WTO’s government procurement procedures and a succinct analysis of the findings of shortcomings by the Independent Inquiry into United Nations procurement for the Iraq Oil-for-Food Programme. The accountability of the United Nations for its far-flung procurement actions is considered not to meet international legal requirements. As a remedy against disregard of established procedures – which may be caused by political interventions – the author recommends, inter alia, to open a venue for claims and objections by bidders under a rapid challenge procedure.