Valued aide meets extremely upset constituents (8)
I believe the answer is:
esteemed
'valued' is the definition.
('esteem' can be a synonym of 'value')
'aide meets extremely upset constituents' is the wordplay.
'constituents' says the answer is hidden in the clue (I've seen 'constituent' mean this).
'upset' shows that the letters should be reversed in order.
'demeetse' can be found hidden inside 'aide meets extremely'.
'demeetse' backwards is 'ESTEEMED'.
(Other definitions for esteemed that I've seen before include "Meet seed being thought well of" , "Had great respect for" , "Venerable" , "Respected and appreciated like customer" , "Highly thought of, respected" .)