The Efficient Markets Hypothesis is one of the most controversial and hotly contested ideas in all the social sciences. It is disarmingly simple to state, has far-reaching consequences for academic pursuits and business practice, and yet is surprisingly resilient to empirical proof of refutation. Even after three decades of research and literally thousands of journal articles, economists have not yet reached a consensus about whether markets - particularly financial markets - are efficient or not. These two volumes bring together some influential articles surrounding the Efficient Markets Hypothesis debate, from Paul Samuelson's pathbreaking proof that properly anticipated prices fluctuate randomly to Fischer Black's study of noise traders, from Eugene Fama's empirical implementation of Efficient Market Hypothesis to Robert Merton's analysis of stock price volatility.