As market leader B&Q starts to square up to increasingly credible competition in the DIY sector, who has their finger closest to their customers' pulse? Retail is a highly competitive business. A retailer's performance is subject to a myriad of factors which serve to boost or dampen growth, from overall economic performance to deflationary pressure from rivals and operating cost inflation. But the principal driver behind performance is also the most difficult to measure - customers and their fluid, evolving opinions. These opinions drive customer behaviour, and ultimately sales and profits. As such, the customer is the single most important element of the retail equation. The Index we have devised is the only available system of performance benchmarking which is defined by the customer. It measures how satisfied customers are with the retailers they use, and as such allows you to really understand your customers - and your rivals'. The Consumer Satisfaction Index 2005 sector report: DIY covers five retailers: B&Q; Homebase; Focus; Wickes and Wilkinson.