Sympathy in harbour following strike (7)
I believe the answer is:
rapport
'sympathy' is the definition.
(rapport is a kind of sympathy)
'harbour following strike' is the wordplay.
'harbour' becomes 'port' (I've seen this before).
'following' means one lot of letters go next to another.
'strike' becomes 'rap' (rapping is a kind of striking**).
'port' put after 'rap' is 'RAPPORT'.
'in' is the link.
(Other definitions for rapport that I've seen before include "Bond of sympathy" , "Feeling of mutual understanding" , "Emotional bond" , "Harmonious and understanding relationship between people" , "Empathy" .)