OFPS Principles of Economics is a text for students who are pursuing a certificate or diploma in polytechnics in Malaysia. It is written based on the latest Malaysian polytechnic syllabus. This book provides a succinct exposition of the essential aspects in microeconomics and macroeconomics such as demand and supply, market equilibrium, theory of production, elasticity of demand and supply, market structure and the determination of price and output, and national income. The subject is presented in systematic manner with suitable tables and illustrations to facilitate quick comprehension. Each chapter ends with a summary and exercise questions. Two model exam papers are provided at the end of the book. Answers are also provided.