Concrete motorway doing for the country (5)
I believe the answer is:
realm
'the country' is the definition.
(I've seen this before)
'concrete motorway' is the wordplay.
'concrete' becomes 'real' (associated in meaning).
'motorway' becomes 'M' (as in motorway names - M1, M4 etc).
'real'+'m'='REALM'
'doing for' is the link.
(Other definitions for realm that I've seen before include "Kingdom; field of interest" , "region" , "Land under a king or queen" , "King's domain" , "Area of knowledge under discussion" .)