Research on the determinants of condom use in sub-Saharan Africa has focused on the personal characteristics of individuals and, more recently, on community characteristics such as levels of development and of contraceptive availability. Two additional community characteristics, however—the restraining influence exerted by social networks and traditional community institutions (both theorized to decline with population growth) and the degree of interpersonal communication concerning HIV/AIDS — should also be factored into research. This study uses data from the 2003 Zambia Sexual Behaviour Survey and other surveys to conduct multilevel analyses to assess the influence of each of these various characteristics on condom use in Zambia. The results show that condom use increases with interpersonal communication concerning HIV/AIDS, community infrastructural development, and access to condoms, and decreases with population growth rate and density. The findings suggest that condom-promotion efforts should be attentive to community-level social norms, population trends, and informal social relationships and interpersonal communication.