This third edition of Principles of Economics is tailored for the Microeconomics and Macroeconomics subjects at polytechnic institutions in Malaysia. In line with changes to the Economics syllabus, whereby Microeconomics and Macroeconomics are currently taught as separate subjects, the topics in the book relevant to these two areas have been clearly defined. Existing topics have been revised and updated to reflect the wider coverage of each topic, while a new chapter on Economic Growth has been added.