Record endorsements involving Judge back in Balkan capital (6)
I believe the answer is:
skopje
'balkan capital' is the definition.
(capital of Macedonia)
'record endorsements involving judge back' is the wordplay.
'record' becomes 'ep'.
'endorsements' becomes 'oks' (OK is an example).
'involving' is an insertion indicator.
'judge' becomes 'j' (abbreviation for judge).
'back' shows that the letters should be reversed in order.
'ep'+'oks'='epoks'
'epoks' placed around 'j' is 'ejpoks'.
'ejpoks' back-to-front is 'SKOPJE'.
'in' acts as a link.
(Other definitions for skopje that I've seen before include "Macedonia's capital" , "somewhere in Balkans" , "foreign capital" , "Capital of FYR Macedonia" , "capital city" .)