Although research with Non-Governmental Organizations (NGOs) has become an established practice, the process and politics of gaining access to such organizations often remains implicit in methodological literature on qualitative research. Drawing on a systematic comparison of research experiences with advocacy NGOs in Kenya, this article discusses organizational access as a multifaceted process. Based on three case studies that were comparable in set-up and context but yielded different outcomes, we argue that the process of obtaining and maintaining access to NGOs is influenced and shaped by researcher positionality, internal and external gatekeepers, organizational characteristics and research topic, and that these factors should be studied in interaction rather than in isolation. Taken together, these factors determine the process of obtaining and maintaining research access, and consequently the outcome of ethnographic fieldwork with NGOs.