In this article, we apply an extended technology acceptance model (TAM) to explore whether national culture influences a user's perception and use of Internet-based negotiation support systems (NSS). In particular, we are interested in whether different preferences for communication patterns, as we find them for low-context and high-context cultures, influence the use and perception of different NSS support tools. The Web-based system Inspire, which provided data for our analysis has been used by over 2000 entities worldwide in experimental negotiations. Our results show that, based on the need to establish a social context in computermediated negotiations, users from high-context cultures exchange significantly more messages and offers during negotiations than users from low-context cultures. Analytical negotiation support is valued significantly higher by users from low-context cultures than by users from highcontext cultures as this problem-solving approach is more compatible with their preference for direct and task-oriented communication.