Very modern country frequently has concern for others (5,2,3,3)
I believe the answer is:
state of the art
'very modern' is the definition.
(I know this)
'country frequently has concern for others' is the wordplay.
'country' becomes 'state' (synonyms).
'frequently' becomes 'oft' (oft can mean frequently, eg oft-quoted).
'has' is a charade indicator (letters next to each other).
'concern for others' becomes 'heart' (heart can mean care or consideration).
'state'+'oft'+'heart'='STATE-OF-THE-ART'
(Other definitions for state of the art that I've seen before include "incorporating the most up-to-date features" , "Technologically most recent" , "Most up-to-date of its type" , "responsibility of picture restorers" , "concern of museum conservationist?" .)