Couturier needing half of studio? Right! (4)
I believe the answer is:
dior
'couturier' is the definition.
(Christian Dior, luxury fashion house)
'half of studio? right' is the wordplay.
'half of' suggests halving the letters.
'right' becomes 'r' (common abbreviation).
'studio' cut in half is 'dio'.
'dio'+'r'='DIOR'
'needing' acts as a link.
(Other definitions for dior that I've seen before include "Christian ..., couturier" , "Fashion designer Christian, famous for his 1947 New Look" , "French couturier, who created the New Look" , "Fashion icon, Christian?" , "French couturier, creator of the New Look in 1947" .)