This article focuses on the challenges of ‘long-delayed’ prosecutions, that is, criminal prosecutions that begin decades after the conflict, using the experience of the International Criminal Tribunal for Bangladesh (ICT-BD) as a case study. This issue is still an insufficiently discussed topic even though such prosecutions are likely to become more common in the future. The focus of this article is mainly on the legal and broader, transitional justice challenges of long-delayed prosecutions at the ICT-BD. The article examines how such prosecutions have had a contradictory, two-fold effect: on the one hand, they have partially broken the endemic culture of impunity that was allowed to prevail for decades in Bangladesh. On the other hand, however, they have been highly controversial and may have served to deepen alienation of the Islamist opposition in Bangladesh. The article concludes that the question of whether long-delayed prosecutions are desirable for a particular society remains highly context-dependent and, in some cases, mechanisms other than criminal trials may be better suited to dealing with the past.