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Describe the situation factually.
Express your feelings and perceptions about the situation.
Assert yourself by asking for what you want or by saying no.
Reinforce or reward by explaining the positive effects of getting what you want or need and the negative effects of not getting what you want or need.
Stay mindful. Focus on your goals. Ignore distractions, including threats or attacks.
Appear confident and effective.
Negotiate and offer alternatives.
Protect yourself
Limiting your exposure to the narcissist is ideal, according to Miller.