The relationship between international crimes and sovereign immunities has bedevilled judicial practice and legal scholarship and created an apparently irreconcilable tension between the two notions. Part of the difficulty in addressing this tension derives from the approach to resolving it. This paper proposes a novel approach, viewing the relationship specifically from the perspective of international criminal law and looking at the three core functions of immunities in that context. The authors conclude that customary international law excludes immunities as defence or bar to jurisdiction for core international crimes regardless of the nature of the jurisdiction concerned, the position of the accused, or the capacity in which the accused acted. When interpreted within that framework, the  ICC  Statute provides for clear limitations to the role of immunities in  ICC  proceedings and avoids the pitfalls that have thus far marred the  ICC ’s approach to the law of immunities.