Clothing industry fashion shoot is back inside (3,5)
I believe the answer is:
rag trade
'clothing industry' is the definition.
(I've seen this before)
'fashion shoot is back inside' is the wordplay.
'fashion' becomes 'rage' (something all the rage is fashionable).
'shoot' becomes 'd'art' (synonyms).
'is back' is a reversal indicator.
'inside' means one lot of letters goes inside another.
'dart' backwards is 'trad'.
'rage' placed around 'trad' is 'RAG TRADE'.
(Other definitions for rag trade that I've seen before include "Clothing business (colloq.)" , "Clothing business (informal)" , "newsagent's business?" , "Slang for the garment industry" , "The couture business" .)