Employer reveals strategy (4)
I believe the answer is:
ploy
'strategy' is the definition.
(I've seen this in another clue)
'employer reveals' is the wordplay.
'reveals' indicates the answer is hidden within the clue.
'PLOY' is hidden within 'employer'.
(Other definitions for ploy that I've seen before include "Game manoeuvre" , "Ruse, stratagem" , "Trick" , "Clever tactic" , "Cunning tactic" .)