Case involving European institute (6)
I believe the answer is:
create
'institute' is the definition.
(I've seen this before)
'case involving european' is the wordplay.
'case' becomes 'crate' (I've seen this before).
'involving' means one lot of letters goes inside another.
'european' becomes 'e' (abbreviation e.g. EU).
'crate' going around 'e' is 'CREATE'.
(Other definitions for create that I've seen before include "Manufacture, bring into being" , "Appoint" , "Make or invent" , "Make, Porduce" , "Build" .)