In this essay I examine the figure of dissident thought in the contexts of philosophical, jurisprudential and political thought. I connect dissidence to the concept of dissent and its linguistic cognates including "disagreement" and "opposition," but also the logic of negation in order to examine dissent as a condition of discourse. In the second and third sections I argue for dissent as a philosophy of non-agreement and review a theory of dissent in law. Finally, I speculate on the history of dissent and dissidence from local contexts to its first wave of global protest with the development of new social movements and the counter-culture of the 1960s and 1970s in order to postulate the changed conditions of dissent in a global, digital, mediatized world. In a postscript I ask whether there are a set of counter-conducts (Davidson, 2011) or counter-practices that can encourage a second wave of global protest, new forms of civic engagement and disobedience.