Balance cost in Europe being reorganised (12)
I believe the answer is:
counterpoise
'balance' is the definition.
('counterpoise' can be a synonym of 'balance')
'cost in europe being reorganised' is the wordplay.
'being reorganised' is an anagram indicator.
'cost'+'in'+'europe'='costineurope'
'costineurope' anagrammed gives 'COUNTERPOISE'.
(Other definitions for counterpoise that I've seen before include "Offset" , "balance" , "Balancing factor" , "Weight balancing another" .)