The civil rights and other social justice movements, neighborhood watches, local garden cooperatives, and so forth are examples of a grassroots context that is largely understudied in CSCW. In recent history, movements to fight child sex trafficking, end hunger in New York City, advocate for financial reform, or even overthrow governments have illuminated a context of grassroots coordination that is a significant departure from the focus of prior research. In contrast to traditional CSCW research contexts, grassroots movements tend to emerge from the local community rather than the corporate. In this context, the information and communications technologies (ICTs) tend to be consumer-grade off-the-shelf tools often administered and supported by a volunteer cadre of varying skill, ability, and availability. But while we see that informally organized, grassroots groups have shown considerable interest in ICTs, the actual effectiveness of ICTs for these groups remains largely unknown. The combined complexity of the ICT technology landscape and grassroots interorganizational networks raises a number of unanswered questions. Therefore, my goals in this research were twofold. First, I sought a rigorous understanding of the current inter-group information sharing practices of nonprofit social justice organizations. Second, I sought to understand how ICTs might best be applied by these organizations in pursuing their missions. Thus, the research question that guided my work was: "In the context of grassroots movements, how do interorganizational networks of nonprofits engage in informal information sharing and coordination, and how can ICTs support this engagement?" In order to address this research question, I examined organizations involved in fighting child sex trafficking. This particular category of nonprofit, social justice organization as a field site was especially suited to this research because the challenges of interorganizational coordination are especially clear, as the inherent complexity of this issue requires many organizations, often with very different structures, backgrounds, and scales, to coordinate together. My dissertation research included two phases of exploration and utilized a combined methodology of field study and user-centered design work. In the first phase, I focused on understanding information sharing practices of anti-trafficking organizations, which led to a more in-depth study of a particular network of organizations and their practice of information sharing for connecting. In the second phase, I conducted a design study within one organization (that I call BridgeOrg) to explore aspects of ICT support in this context. For Phase I of my research, the specific question I addressed is as follows: "RQ 1: What are current information sharing and coordination practices of interorganizational networks in grassroots movements? Also, what challenges do they encounter in information sharing and coordination? And what are their challenges in terms of ICT use and appropriation?" To address this question, I conducted two field studies. My primary purpose in conducting the first field study (Field Study I) was to gain familiarity with the issue of child sex trafficking by examining the broader context of human trafficking and ICT use among organizations fighting this issue. For Field Study II, I chose to focus more specifically on understanding how organizations focused on victim prevention, and BridgeOrg in particular, utilized and appropriated ICTs in their practice of information sharing for connecting. My goal was to conduct a more in-depth field study, with a particular focus on BridgeOrg, to understand the specific information sharing for connecting as they negotiate among themselves what actions to take as network of organizations. In Phase 2 of my research, I conducted two design studies to address the specific question below: "RQ 2: In the context of grassroots movements, what features of ICTs might better support interorganizational networks in their information sharing and coordination?" The first design study was to employ a user-centered approach to re-design the existing custom website to explore a network-centric design of information structure, presentation, and production. This website was designed to support BridgeOrg's practice of information sharing for connecting. In the second design study (Design Study II), I focused on creating a novel approach using applied visualization for informing basic awareness in BridgeOrg's network using a folksonomy that was identified in my field studies. My research yielded the following contributions: 1) An understanding of the challenges in information sharing, and ICT use and appropriation for grassroots organizations. 2) Insight into the information sharing practices among grassroots organizations, and their ICT use and appropriation mediates such practices. 3) Exploration of network-centric ICT design to support informal information sharing and coordination. 4) A novel visualization approach to support network-centric navigation and exploration of a grassroots network of organizations. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. 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