New research emphasises the need to conceptually differentiate authoritarianism on right and left from conventional conservatism and liberalism. It is therefore argued that authoritarianism is best conceptualised as an intolerant and morally absolutist motive to coercively impose particular values, way of life, and social organisation on individuals. Research on likely causes and consequences has thus far focused almost entirely on authoritarianism of the right, and indicates that two distinct dimensions, best captured by Right Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO), have different genetic, dispositional, and situational origins. In addition, despite having broadly similar likely effects on anti-democratic attitudes, prejudice, nationalism, political intolerance, and extremism, they are differently motivated; RWA by perceived threats to safety and security, and SDO by competitive threats to the social hierarchy. Emerging research on LWA also suggests that authoritarianism of both right and left are rooted in similar personal characteristics and have similar effects on attitudes and behaviour.