Review of Situational LeadershipÂŽ After 25 Years - A Retrospective (Blanchard, Zigarmi, & Nelson, 1993) The situational leadership theory holds that leaders should change their style based on the competence and commitment of followers. This prĂŠcis critiques Blanchard, Zigarmi, and Nelson's (1993) research article on the subject, which offered a 25-year retrospective of the Situational Leadership Model, one of the more widely recognized approaches to leadership. Olivier Serrat 19/05/2018