Effect is perfect (8)
I believe the answer is:
complete
This clue is a double definition.
'effect' is the first definition.
(I know that complete is a kind of accomplish)
'perfect' is the second definition.
(perfect and requiring no additional changes)
'is' acts as a link.
(Other definitions for complete that I've seen before include "Having all the necessary parts" , "Intact" , "Full" , "Whole, nothing missing" , "Finish; whole" .)