Bring about; timely (6)
I believe the answer is:
prompt
I believe this clue is a double definition.
'bring about' is the first definition.
(I've seen this before)
'timely' is the second definition.
(synonyms)
(Other definitions for prompt that I've seen before include "Precisely on time" , "Punctual; instigate" , "Bang on" , "Encourage" , "Supply a forgotten line to an actor" .)