Good man, formerly capital in public relations (5)
I believe the answer is:
prior
'good man' is the definition.
'prior' can be an answer for 'man' (I have seen 'holy man' mean 'prior' so perhaps 'man' could also mean 'prior'). I'm unsure of the 'good' bit.
'formerly capital in public relations' is the wordplay.
'formerly capital' becomes 'rio' (I've seen this before. I am not sure about the 'formerly' bit.).
'in' indicates putting letters inside.
'public relations' becomes 'PR' (abbreviation).
'rio' going within 'pr' is 'PRIOR'.
Can you help me to learn more?
(Other definitions for prior that I've seen before include "Coming before N a superior" , "More pressing" , "Previous; abbot's deputy" , "writer of epigrammatic verse" , "Previous - religious leader" .)