Strong drive for success (8)
I believe the answer is:
ambition
'strong drive for success' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ambition that I've seen before include "hope for the future" , "Desire to succeed in life" , "A determination to succeed" , "Strong desire for success" , "I'm in boat (anag.)" .)