Vital work by a new European (7)
I believe the answer is:
latvian
'european' is the definition.
(someone from Latvia)
'vital work by a new' is the wordplay.
'work' is an anagram indicator.
'by' means one lot of letters go next to another.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'vital' is an anagram of 'latvi'.
'latvi'+'a'+'n'='LATVIAN'
(Other definitions for latvian that I've seen before include "who lives in ex-Communist country?" , "Riga resident" , "From one Baltic state" , "Baltic national" , "Baltic language" .)