Bring on, cause to happen (6)
I believe the answer is:
induce
This clue is a double definition.
'bring on' is the first definition.
(I know that bring on can be written as induce)
'cause to happen' is the second definition.
(inducing is a kind of causing to happen)
(Other definitions for induce that I've seen before include "Give rise to" , "Bring on by artificial means" , "Persuade, hasten childbirth" , "Bring on, cause to happen" , "Persuade or bring on, say birth" .)