This dissertation studies partnerships among non- governmental organizations (NGOs) and the resulting consequences of these collaborations. The presence of NGOs in the international system is recognized with scholarly works examining what they are, what they do, and what is their role. However, it is also necessary to systematically analyze the causes for collaborations among NGOs and the following consequences. I ask what determines for NGOs to partner with one another. And, who benefits from these collaborations? I carefully place my study within the broader context of the main international relations paradigms and within the specific debates concerning the NGOs. Using social network analysis, quantitative tools, and in-depth interviews I find that similarity is a main determinant for NGOs to collaborate with one another. Importantly, my findings show that not only shared altruistic goals, as proposed by the dominant literature, but also shared strategic goals matter in the choices for partners. I further show that shared altruistic and strategic goals also influence who the final beneficiaries from the collaborations are. My findings reveal that less often vulnerable populations receive a direct help, even when the organizations advance principled goals. I conclude that NGOs have not only altruistic goals but also strategic needs and wants. The forging of their partnerships and the outcomes of their collaborations are influenced by these distinct goals. NGOs, as strategic actors, make complex decisions, that momentously bring a limited impact on vulnerable populations and the international system overall.