In recent times there is no dearth of elegant works dealing with the subject of Quantum Mechanics at the undergraduate and postgraduate level. There are, however, few books written in a form which focus attention on all the important concepts of Quantum Mechanics that hold the interest of the inquisitive student. There are fifteen chapters in this book. In the explanation of various concepts covered in this book, the attepmt has been made to describe them in the light of modern developments in a simple language and elegant style. Wherever necessary a large number of solved numerical problems have been given to help the student in understanding the concepts more clearly. A special feature of the book is that the text has been illustrated with a large number of figures and the data presented in the form of numerous tables for reference and comparison.