historically, the epidemiology of sexually transmitted diseases (std) has been based on individual attributes and behavior. however, std constitute a good example of diseases that depend on personal contacts for dissemination. social network analysis is a relatively new technique that studies the interactions among people. since 1985 when it was first used for std, some studies have been done using the technique, especially in the last 10 years. the two network-based designs, sociocentric or complete networks and egocentric or personal networks, are currently recognized as important tools for a better understanding of std's dynamic. here an overview is presented of social network analysis: the technique, its use, and its limitations. ethical considerations regarding social network analyses are also briefly discussed.