Biodun and his project partner Sade have been working together on a school assignment. Biodun is frustrated that Sade keeps missing deadlines. When they finally meet to discuss it, Biodun says: you are not taking this seriously. Sade replies: I'm doing everything I can, you just never communicate the real timelines. Within minutes they are arguing not about the project but about who is a good person. This is what Fisher, Ury, and Patton call mixing the people with the problem. And it is one of the most destructive patterns in any negotiation. Their first principle is: separate the people from the problem. Negotiators are human beings before they are representatives, counterparts, or opponents. They have egos, emotions, fears, and deeply held values. When those feelings get tangled up with the substance of the negotiation, both the relationship and the outcome suffer. The authors identify three categories of people problems. Perception. We each see the situation from where we sit. A landlord and a tenant negotiating rent renewal can look at the exact same apartment and have completely opposing views of what is reasonable — and both can be sincere. The gap is not dishonesty; it is perspective. The most important skill here is to genuinely try to understand how the other side sees it — not as a tactic, but because understanding their view is the only way to bridge it. Emotion. In a difficult negotiation, feelings may be more important than facts. Acknowledge emotions — yours and theirs — rather than suppressing them. When someone feels unheard, they stop engaging with the substance. Something as simple as: I understand this is frustrating — can open a door that logic alone cannot. Communication. Most misunderstanding in negotiations is not about facts but about what was heard. People talk past each other. People assume. People react to what they feared would be said rather than to what was actually said. Active listening — paraphrasing, asking clarifying questions, checking understanding — costs nothing and prevents most of the derailment that comes from communication breakdowns. The authors' instruction is not to ignore people problems but to address them directly and separately from the substance. Deal with the relationship on its own terms. Then deal with the issue on its own terms. Do not use one as leverage on the other.