31. Stone Group - £65.5m

The Staffordshire system builder was one of a number of firms to suffer at the hands of public sector cutbacks in 2011, as sales declined six per cent. The company suffered from the loss of £6.6m in sales garnered from the Home Access scheme and other one-off projects undertaken in the prior year. But operating profit actually grew by more than £500,000 in FY11, rising to £1.9m.