Many studies of ego-centered networks have aimed to obtain proxies for networks that help estimate their size and nature. As an alternative, the contact diary offers a comprehensive approach that records and yields archives of actual and comprehensive networks. In the long run, the actual and dynamic data from contact diaries can provide researchers with a potential baseline and delineate total or global personal networks within a specific time frame. This article explains how to use the diary approach to collect network data. After a review of studies that have adopted diaries in general and contact diaries in particular, I then discuss a recent diary study's research design in more practical terms. Finally, I appraise some advantages and limitations of the approach and explore other uses of contact diaries, such as building archives of year-long, active networks.