Agile requirements engineering implies more complex communication patterns since even the developers are supposed to have direct contact with customers. With more face-to-face communication comes social-psychological factors influencing the requirements. Studies have pointed at the importance of negotiation training, but I argue that more basic human traits can be triggered in favor of the negotiator with the most knowledge of social influence research and practice. I suggest a plan of how research in social influence and requirements facilitation can be conducted, mostly through experimentation.