Some of the shops I like for work clothes are:
Hobbs
Reiss when the cut of clothes isn't too youthful
Boden for the occasional plain dress, none of their crazy patterns
Jigsaw as long as I can bung it in the washing machine
L K Bennett but I can only justify spending that sort of money on one dress a year
White Stuff occasionally when there is something smarter in
Where else should I be looking?