1Before someone has said a word, you have often already decided what they are: only here because they were made to come, not really interested, wasting your time. That decision changes how the meeting goes.
The person sent by a court, or pushed into the room by a partner or a manager, walks in already read. Try starting the hour with nothing written: no history of what people like this are usually like, no forecast of how it will end. Notice the moment you catch yourself predicting them, and go back to what they are actually saying. This is as much for anyone meeting a difficult relative as for a clinician.
Islamic evidence
If they turn away, say, God is enough for me: there is no god but Him; I put my trust in Him (Quran 9:129). Even someone turning away is met with trust rather than with a verdict about them.
“If they turn away, [Prophet], say ,‘God is enough for me: there is no god but Him; I put my trust in Him; He is the Lord of the Mighty Throne.’”
Qur'an 9:129
Psychological evidence
In a cross-sectional study using structural equation modelling, higher trait mindfulness went with less anger, hostility and aggression, and lower rumination partly explained the link. The relevant piece is that hostility travels with a habit of mind, which applies to the helper in the room as much as to anybody else. The data were gathered at a single point in time, so this shows what goes together, not what causes what.
Borders A, Earleywine M, Jajodia A. (2010). Aggressive behavior · doi
Review detail
Why it works. People can feel when you have already made your mind up, and they behave like the person you expect.