New title about way of working provided recurring theme (9)
I believe the answer is:
leitmotif
'recurring theme' is the definition.
(I've seen this before)
'new title about way of working provided' is the wordplay.
'new' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'way of working' becomes 'mo' (abbreviation for modus operandi).
'provided' becomes 'if' (eg 'provided it's sunny' means 'if it's sunny').
'title' with letters rearranged gives 'leitt'.
'leitt' placed around 'mo' is 'leitmot'.
'leitmot'+'if'='LEITMOTIF'
(Other definitions for leitmotif that I've seen before include "A melodic phrase that accompanies the reappearance of a person on stage" , "Recurring theme in literary composition" , "it's a repetitive strain" , "Recurring musical theme" , "Recurrent theme" .)