In this chapter, we discuss how culture influences computer mediated communication (CMC). We use an Input-Process-Output (I-P-O) model as a theoretical framework to analyze relationships between culture and CMC. We describe three dimensions of cultural variability—individualism/ collectivism, low vs. high context of communication, and task- vs. relationship-orientation—and describe how these dimensions influence people’s reliance on features of CMC. A review of the literature to date suggests that cultural factors do indeed shape how people use CMC. More specifically, auditory and visual cues appear to have more importance for members of collectivistic, high-context, relationship-oriented cultures than they do for members of individualistic, lowcontext, task-oriented cultures. However, further research is needed to clarify relationships between cultural dimensions and CMC, to understand the role of moderating variables such as gender of participants, task, and group composition, and to provide design guidelines for new tools to support intercultural communication and CMC in developing regions.