VIP raves possibly about end of surveillance that's widespread (9)
I believe the answer is:
pervasive
'widespread' is the definition.
(I've seen this before)
'vip raves possibly about end of surveillance' is the wordplay.
'possibly' is an anagram indicator.
'about' is an insertion indicator.
'end of' indicates one should take the final letters.
The final letter of 'surveillance' is 'e'.
'vip'+'raves'='vipraves'
'vipraves' with letters rearranged gives 'prvasive'.
'prvasive' enclosing 'e' is 'PERVASIVE'.
'that's' acts as a link.
(Other definitions for pervasive that I've seen before include "Widespread" , "Spreading throughout" , "Widely-spread" .)