Prior research has suggested gender differences in negotiation outcomes, particularly when parties are advocating for themselves in a fixed pie (distributive negotiations) context (Walters, Stuhlmacher, & Meyer, 1998; Stuhlmacher & Walters, 1999; Mazei, Hüffmeier, Freund, Stuhlmacher, Bilke, & Hertel, 2015). On average, male negotiators walk away with significantly more value than female negotiators. What is left unanswered is how much of any gender difference is due to party’s own behavior (men and women making different opening offers and conceding at different rates) and how much is due to the other party’s reaction towards different genders (men and women making different opening offers and conceding at different rates depending of the gender of their counterpart). We have designed a 2 (true gender) X 2 (assigned gender) virtual reality study whereby we can disentangle processes and outcomes related to “true” gender from those related to “assigned” gender. We will have essentially 4 conditions: 1) true and assigned gender male, 2) true and assigned gender female, 3) true gender male and assigned gender female, and 4) true gender female and assigned gender male. This allows us to disentangle supply side effects (own behavior) from demand side effects (expectations about and reactions to the other party because of gender), and to see how much each might contribute to negotiation processes and outcomes.