This article concerns the problem of time in the sphere of development and functioning of the contemporary international criminal courts and tribunals. The temporal aspects were analysed mostly in relation to the International Criminal tribunal for Yugoslavia, International Criminal Tribunal for Rwanda and International Criminal Court. Their genesis, character and ratione temporis jurisdiction have been described from the perspective of time factor. In area of development of contemporary criminal tribunals a certain period of time seems to be the sine qua non condition for formulating states’ common will concerning creation of international organs of such nature. It is especially important in relation to organs of permanent character (ICC). It is also worth noting that a factor of time lets describe international criminal courts and tribunals as permanent or temporary which seems to be linked with the scope of their temporal jurisdiction. In this way the time factor seems to penetrate and infl uence the functioning of international criminal courts in all important areas of their genesis and their activity.