Man in silk changing foreign capital (8)
I believe the answer is:
helsinki
'foreign capital' is the definition.
(I've seen this before)
'man in silk changing' is the wordplay.
'man' becomes 'he' (pronoun for a man).
'changing' is an anagram indicator.
'in'+'silk'='insilk'
'insilk' is an anagram of 'lsinki'.
'he'+'lsinki'='HELSINKI'
(Other definitions for helsinki that I've seen before include "Finland's capital" , "Nordic capital" , "Capital of Finland" , "Foreign city" , "Nineteen fifty two Olympics city" .)