Assist a CEO working with colleagues (10)
I believe the answer is:
associates
'colleagues' is the definition.
(I've seen this before)
'assist a ceo working' is the wordplay.
'working' is an anagram indicator.
'assist'+'a'+'ceo'='assistaceo'
'assistaceo' with letters rearranged gives 'ASSOCIATES'.
'with' acts as a link.
(Other definitions for associates that I've seen before include "Colleagues" , "Hangs out with" , "Companions" , "mates" .)