Captain of industry in public house, working (5)
I believe the answer is:
baron
'captain of industry' is the definition.
'public house working' is the wordplay.
'public house' becomes 'bar' (I've seen this before).
'working' becomes 'on'.
'bar'+'on'='BARON'
'in' acts as a link.
(Other definitions for baron that I've seen before include "Lowest rank of British peerage" , "Noble rank" , "A born nobleman" , "powerful man owning lots of dailies?" , "British peer of the lowest rank" .)