After selling more than 100,000 copies in its previous editions, this 6th edition of ECONOMICS: AN INTRODUCTION continues its tradition of providing college students with the basic principles of economics through Macroeconomy or Economics of a Nation. As in previous editions, the book seeks to blend modern economic theory with Philippine facts and issues, making the learning process easier and more relevant.  It also puts a clear development orientation to an introductory course, by tackling growth and developmental issues through most of the book.  Needless to say, the book reflects the changing science of economics. It was the first to introduce the aggregate supply function more explicitly in its second edition, and continues to introduce newer theories and approaches of the science. This book thoroughly updates the reader not only in the theories, but also in the data available and research carried out in the field, particularly on the Philippine economy.