This document discusses the role of perception in negotiation. It explains that perception is how individuals interpret their environment to respond appropriately, but there can be errors since perception depends on one's state of mind. Negotiators' perceptions guide them in negotiations. There are several perceptual errors that can occur, like stereotyping, halo effects, selective perception, and projection. The document also discusses frames in negotiation, individual and competitive biases, and how emotions can impact negotiations. It provides references for further research on topics like social perception, sacred issues, and cultural differences in perception.