Sir; The notion that supermarket strategies centre on catering for a discrete sub-set of the population is increasingly an over-generalisation.

Shoppers use a variety of different supermarket chains and choice will depend on circumstances. They may pop down the road to the Sainsbury's Local for milk, visit Asda at the end of the month when funds are low and hit Tesco on a Friday to pick up wine and a Finest meal.

Understanding the profit potential of these missions and what motivates us to choose one store over another allows supermarkets to make the most of their money-making potential.

What we are likely to see is Tesco, Asda and Sainsbury profiling localities not just in terms of who lives there but in terms of the circumstances driving people to shop. Each store can then be adapted to cater to the most prevalent and profitable missions occurring in the area.