DNA replication plays an essential role in all life forms. Research on archaeal DNA replication began about twenty years ago. Progress was hindered, however, by the lack of genetic tools to supplement the biochemical and structural studies. This has changed, however, and genetic approaches are now available for several archaeal species. One of these organisms is the thermophilic euryarchaeon Thermococcus kodakarensis. Here the recent developments in the biochemical, structural and genetic studies on the replication machinery of T. kodakarensis are summarized.