Picture hospital department following almost complete success (10)

'success' is the definition.
(succeeding in a goal)

'picture hospital department following almost complete' is the wordplay.
'picture' becomes 'film' (synonyms).
'hospital department' becomes 'ENT' (Ear, Nose and Throat).
'following' means one lot of letters go next to another.
'almost' means to remove the last letter (most of the word but not all of it).
'complete' becomes 'full' (similar in meaning).
'full' with its final letter taken off is 'ful'.
'film'+'ent'='filment'
'filment' put after 'ful' is 'FULFILMENT'.