The Journal of Social Structure (JoSS) is an electronic journal of the International Network for Social Network Analysis (INSNA). It is designed to facilitate timely dissemination of state-of-the-art results in the interdisciplinary research area of social structure. It publishes empirical, theoretical and methodological articles. Articles are accepted only after peer review. Comments, rejoinders and extensions on already published articles will be peer-reviewed and if accepted will be attached via a hyperlink to the previously published piece. All published articles and comments (including embedded data, graphics, algorithms and simulations) are permanently archived by the library at Carnegie Mellon University.