Research on high-reliability organizations was originally carried out with aircraft carriers and nuclear submarines. Essentially, this involved relatively closed communities, with a high operational tempo at which mistakes could have extremely serious and direct consequences. In these cases, rapid learning was a byproduct of personnel rotation and the need to train successors. Recent research suggests that high-reliability organizations have five important characteristics: a preoccupation with failure, a reluctance to simplify, sensitivity to operations, resilience, and a respect for expertise. It is not immediately obvious that these qualities are an inherent part of the culture of the organizations that manage drilling operations today. The thesis of this paper is that these five traits taken together can prevent drilling operations from drifting into failures caused by the complexity of the organizations involved in conceptualizing, planning, and executing drilling operations, including the management environment in which they are set. This paper considers how apparently successful organizations can "drift into failure," in part, as a result of the consequences of organizational complexity. These ideas set the scene for a review of high-reliability-organization theory and suggest ways in which the principles might be applied to the management of drilling operations.