This Business Economics book is the outcome of my experience of four decades of the teaching of microeconomics to graduate and post-graduate students of Indian universities. It is intended as a comprehensive text for them. Besides, it will be useful to students of commerce and business administration as well. With the decay of communism and re-enthroning of the market economy, it has become even more important to understand the function of the market as a co-ordinating system. Joan Robinson described the economic theory as a ?box of tools?. For proper handling of our tools, we must learn how they function. This book fulfils these objectives. I have tried to present a clear and accurate picture of modern microeconomics. While doing this, relevant historical account has also been added so that the principles of modern economics are understood in their proper perspective. Though the book has been presented in the traditional format, the analysis covers all important recent developments.