Give satisfaction, if you'd be so kind (6)
I believe the answer is:
please
This clue is a double definition.
'give satisfaction' is the first definition.
(I've seen this before)
'if you'd be so kind' is the second definition.
(Other definitions for please that I've seen before include "Satisfy or gratify" , "Give pleasure to (someone)" , "Make glad, being asleep" , "Want" , "Gratify as by a sleep" .)