Edited by Profs. Day and Montgomery. A special issue of Journal of Marketing Vol. 63, 1999. Deals with Fundamental Issues and Directions for Marketing in the Twenty-First Century. The published papers reflect the winning entries from a much larger set. The issues are divided into four major sections dealing with fundamental questions: I. How Do Customers and Consumers Really Behave? , II. How Do Markets Function and Evolve? III How Do Firms Relate to Their Markets? , and IV. What Are the Contributions of Marketing to organizational Performance and Societal Welfare?