Inspite of the fact that there is a desire among chemist to learn the intricacies of the group theory and its applications, a few of them could learn it. It is all because, the Group Theory is considered a difficult subject as it desperately requires a mathematical background and the sixth sense of imagination. An effort has been made here to minimize the mathematical part. The book starts with a simple background of Symmetry Elements, Group Theory, Matrix Algebra etc. and then it is development to give some chemical application like d-Block Elements, Term Symbols, Hybridisation, Symmetry Adapted Linear Combinations (SALC's), Delocalisation Energy, Sandwich Compounds, Molecular Vibrations etc. This book is equally useful to a beginner and to an experienced worker. A novelty of the book is the use of operators instead of symmetry elements.