The problem of natural right is one of the most controversial and important issues in contemporary political and social philosophy. In this classical work, Leo Strauss examines the status of the issue in contemporary thought and argues that there is a firm foundation in reality for the distinction between right and wrong in ethics and politics. On the centenary of Strauss's birth and the fiftieth anniversary of the Charles R. Walgreen Lectures at the University of Chicago, where Strauss first presented the work, the book remains as controversial and essential as ever.