Roberto Mangabeira Unger is a Brazilian contemporary social theorist, philosopher, politician, and law professor whose writings span the fields of social theory, philosophy of law, economics, religion, science, and general philosophy.
Unger was associated with the Critical Legal Studies movement for a brief period in the late 1970s and 1980s. Unger has long been active in Brazilian and South American politics as a candidate, political activist, and advisor to world leaders.