Although people have been negotiating since ancient times, academic research has long overlooked the conversational side of the process. ‘Much negotiation research has focused on offers, concessions, and tactics,’ says Dudenhöffer. ‘But most communication happens beyond words. My research shows how these subtle cues can tip the balance of a negotiation.’

Disappointment helps

Dudenhöffer first looked at the role of emotions. She found that expressing disappointment can often secure better deals, while expressions of happiness or guilt may backfire, encouraging opponents to push harder. This finding challenges the common assumption that displaying positivity always leads to smoother interactions. Instead, certain negative emotions can signal seriousness or dissatisfaction, prompting the other side to make more generous concessions.

Power of clothing choices

Dudenhöffer also highlights the surprising role of appearance. Across four different studies, it was shown that female negotiators received more favourable offers from male counterparts when wearing attire that revealed their femininity compared to more conservative clothing. The results suggest that female clothing choices can trigger subconscious responses in their male negotiation counterparts that influence the offers that are then placed on the table. While these findings raise important questions about bias and professionalism, they underline the real-world power of nonverbal communication.

Influence of voice

Voice proved to be another powerful factor. By analysing recorded negotiations, the research revealed that vocal qualities – such as subtle variations known as jitter and shimmer – shape how negotiators are perceived. These paraverbal cues affected not only rapport between the parties but also the economic outcomes of the negotiations. In today’s era of video calls and remote work, understanding the influence of voice has never been more relevant.

Even the smallest conversational details can matter. Dudenhöffer also examined what happens when negotiators introduce their statements with “behaviour announcements” – phrases like “Let me make you an offer” or “Let me ask you a question”. Some of these brief introductions increased the perception of transparency and often improved rapport between negotiators. While seemingly insignificant, such framing devices can subtly shift how the parties view the negotiation’s progress.

Practical implications

The implications of these findings reach far beyond academia. For professionals, they offer practical insights: negotiators might benefit from expressing disappointment rather than anger, becoming more mindful of how attire shapes perceptions, and paying closer attention to the tone and quality of their voice. For organisations, the research highlights the importance of training employees not just in strategy, but in the nuanced art of communication.

Dudenhöffer intends to explore these dynamics further using new tools such as artificial intelligence and machine learning, which could help analyse subtle conversational patterns at scale. Such methods could deepen our understanding of how human interaction drives success or failure in negotiations.

‘We all have our own realities, which we form on the basis of our perceptions of the world and the people around us,’ says Dudenhöffer. ‘Accordingly, my research shows that negotiation outcomes aren’t determined solely by rational strategies or power dynamics. They are shaped by the everyday signals we send without even realising it – our emotions, our clothing, our voices, our words. By becoming more aware of these signals, we can all become better negotiators.’