In this book, Filimon Peonidis gathers one unpublished and seven published essays that he wrote between 1997 and 2021. The first three refer to the early history of freedom of expression focusing on the work of James and John Stuart Mill and its possible significance in a contemporary setting. The remaining five deal with current issues such as the prerequisites of a free speech theory, defamation, the regulation of pro-terrorist speech, the harsh criticism of religious dogmas as part of religious freedom, and the controversies surrounding campaign financing in the United States. Taken together these essays can be seen as a philosophical exploration of various aspects of freedom of expression, which is here understood as a moral and political value of paramount importance. Filimon Peonidis is Professor of Moral and Political Philosophy at the Aristotle University of Thessaloniki. His research interests include ethics, democratic theory, the history of democratic traditions and freedom of expression.