Business given publicity in Herts town (7)
I believe the answer is:
trading
'business' is the definition.
(thesaurus)
'publicity in herts town' is the wordplay.
'publicity' becomes 'ad' (advert).
'in' means one lot of letters goes inside another.
'herts town' becomes 'tring' (I've seen this before).
'ad' inserted into 'tring' is 'TRADING'.
'given' is the link.
(Other definitions for trading that I've seen before include "Buying and selling" , "Commercial activity" , "Exchanging; a word used in the first ever 2 dn" , "Dealing" , "In business" .)