Bioaugmentation (BA) for oil spills is a much more promising technique than is biostimulation (BS). However, the effectiveness of BA is variable, because the survival and the xenobiotic-degrading ability of introduced microorganisms are highly dependent on environmental conditions. As an alternative, autochthonous bioaugmentation (ABA) is proposed to overcome these difficulties. The ABA method is like a ready-made BA technology. In ABA, microorganisms indigenous to the contaminated site or predicted contamination site that are well-characterized and potentially capable of degrading oils are used, and these microorganisms should be enriched under conditions where BA will be conducted. It is possible to obtain information in advance on the chemical and physical characteristics of potential oil spill sites and of oils that might be spilled. The application of ABA in the coastal areas of Hokkaido Prefecture, Japan, is considered here, becauseHokkaido is located south of Sakhalin Island, Russia, where development of oil fields is in progress.If oil spills in this region were well characterized in advance, ABA could be a feasible technology in the near future..