The post-9/11 environment, in which inter-state and inter-agency cooperation has at times been preferred to the detriment of the security and rights of individuals, is a context that Canada and many European nations share. This broad survey is intended to provide those interested in government investigations into the torture and detention of their citizens abroad with food for thought. The Canadian experience reveals that there are costs associated with the involvement of state officials in the dubious treatment of citizens: costs for institutions, individuals and political parties. Furthermore, there is no doubt that investigations are an essential part of the accountability process and that setting up a process that is independent, public and effective is a significant challenge. The O’Connor and Iacobucci inquiries are important not just because of the themes we can extract from their findings – themes relating to the sharing of information, the training of officials, the provision consular services and other issues found in the experiences of many different countries. They are also important because of the way they sought to balance the elements required for a legitimate and successful inquiry with the demands of confidentiality for national security.