The intension of this book is to present two different proofs of Kneser's Theorem by H.B. Mann and Y.O. Hamidoune. This book provides a fair introduction to both addition theorems and isoperimetric methods on the basis of which they developed two beautiful proof of Kneser's Theorem. Chapters are divided in such a way that readers find no difficulties as all the preliminaries required are covered nicely. Further Generalization of Kneser's Theorem, Application of Kneser's Theorem and Kneser's theorem on non-Abelian groups are also discussed in the last chapter.
