13 Britten Street, SW3 (020-7349 9040).
'Knock, knock.' Who's there? 'Eamonn.' Eamonn who? 'Eamonn Old Etonian.' The Builders is a stratospherically upmarket gastropub in the heart of Chelsea, with Old Etonian types and their birds as clientele. Evenings and Sunday lunches are the best times to meet yer average Sloane.