Throughout history, humans have gathered in groups for social, religious, and industrial purposes. As the conglomeration of people interact, a set of underlying values, beliefs, and principles beams to develop that serve to guide behavior within the group. These "guidelines" are commonly referred to as the group culture. Modern-day organizations, including corporations, have developed their own unique cultures derived from the diversity of the organizational interests and the background of the employees. Safety culture. a sub-set of organizational culture, has been a major focus in recent years. This is especially true in the chemical industry due to the series of preventable, safety-related disasters that occurred in the late seventies and eighties. Some of the most notable disasters, during this time period. occurred at Bhopal, Flixborough, and Seveso. However, current events, like the September 11th terrorist attacks and the disintegration of the Columbia shuttle. have caused ail assessment of safety culture in a variety of other organizations. (c) 2005 Elsevier B.V. All rights reserved.