Top managers have a key role in implementing the environmental component of sustainable development in the organization. This paper presents the results of the unique research that was conducted among top managers from a variety of large Slovenian organizations, in order to determine the dominant leadership factors that positively influence the implementation of the environmental component of sustainable development (the iso 14001 standard) in the organization. The research involved 321 large Slovenian organizations. It was found that vision, credibility, collaboration, accountability and action orientation are the dominant leadership factors to be considered by top managers in achieving sustainable development.