Amazed, and so is the organisation (10)
I believe the answer is:
astonished
'amazed' is the definition.
('astonish' can be a synonym of 'amaze')
'and so is the organisation' is the wordplay.
'organisation' indicates an anagram.
'and'+'so'+'is'+'the'='andsoisthe'
'andsoisthe' anagrammed gives 'ASTONISHED'.
(Other definitions for astonished that I've seen before include "Staggered" , "Confounded" , "dumbfounded" , "Gobsmacked" , "given a bombshell?" .)