To critically review the literature on the impact of differentiation strategies on the market share, sales and EPS of Tesco and Sainsbury’s over a five-year period. •Using the Annual Reports, Financial Statements and Strategic Reports 2014/5 – 2018/9, quantitatively measure the impact on market share and company profitability from the introduction of new products and services over a five-year period. •To explore the main differences of the perceived quality of products used during the Tesco and Sainsbury’s promotional campaigns 2014-2019 using qualitative methods such as commentary from industry experts and YouGov BrandIndex scores.