This book examines and explains the current situation and problems of supermarket chains in England. Supermarket chains are operating in a profitable market but they are confronted with the problem of high competition and compared to manufacturers they have only few possibilities to differentiate. Especially the importance of differentiation is questioned in this book. It is examined whether differentiation is really essential for gaining competitive advantage. For a comprehensive and substantiated demonstration secondary theoreatical data and a study with primary data is used. With theories of manufacturers and retailers possibilities for differentiation are identified. Aspects of customer perceptions are considered as important as differentiation and thus, included and linked to differentiation strategies. A study ascertained best practice by surveying students to examine perceived differentiation factors. Upon critical success factors perceived added value is identified as a major issue of differentiation strategies and included in this study. The research led to the fact that differentiation is not conducted by all supermarkets and that undifferentiation can also be a profitable strategy. Hence, positioning strategies solely based on differentiation is seen as inadequate. For a successful applied competitor based strategy a combination of differentiation types, price and differentiation interdependencies, market segmentation and customers' critical success factors is suggested.