You and I have success in shade (5)
I believe the answer is:
white
'shade' is the definition.
'you and i have success' is the wordplay.
'you and i' becomes 'we'.
'have' means one lot of letters goes inside another.
'success' becomes 'hit' (hit is a kind of success).
'we' placed around 'hit' is 'WHITE'.
'in' is the link.
(Other definitions for white that I've seen before include "murderer" , "Policy statement" , "Outer part of egg" , "Reflecting virtually all light" , "See 10" .)