Get on with Charlie in New York bureau (6)
I believe the answer is:
agency
'bureau' is the definition.
(synonyms)
'get on with charlie in new york' is the wordplay.
'get on' becomes 'age' (synonyms).
'with' says to put letters next to each other.
'charlie' becomes 'c' (phonetic alphabet: alpha, bravo, charlie etc.).
'in' is an insertion indicator.
'new york' becomes 'ny'.
'c' placed into 'ny' is 'ncy'.
'age'+'ncy'='AGENCY'
(Other definitions for agency that I've seen before include "Business that serves other businesses" , "Through which something is accomplished" , "Business providing specific service" , "Intervention producing a particular effect" , "Office or business of one who does business for others" .)