Based on case studies of Japanese interventions in Senegal, this contribution aims at examining the relationships and controversies existing between the different actors involved in the world of humanitarian assistance and development aid. These include: scholars (researchers, experts, students...), NGO workers, agents and volunteers from governmental organizations (JICA) and international organizations (UNICEF, Oxfam...).Today, all these actors regularly work on the same field at the same time. Academics as well as local and international NGOs have contributed to the development of Africa, creating knowledge about local societies, suggesting if not sometimes helping build new development aid strategies, while producing know-how that is very often collected with the support of members belonging to these local communities.Local NGOs play a critical role in these relationships. Part and parcel of Senegalese society and managed by Senegalese people, they are not only contributing to the economic and social development of their country, but they are also playing the role of “fixers” for foreign scholars and agents, helping them link with other local actors and groups living in the different regions of Senegal.However, the presence of various Japanese stakeholders, be they academics, NGO workers, government or private companies representatives, may confuse Senegalese citizens because despite they actually work in the same areas and often deal with the same kind of issues; education, health, poverty or good governance, each group develop their own strategies and have their own political and philosophical views. If the purpose of NGOs or that of government agencies is summed up in the word "action" that leads to direct interventions on the field, the scholar's objective is the result of his/her academic research. Scholars work to build, or to discover, a new knowledge that will contribute to the academic community of developed countries, even if in some cases, the results of their research may have a practical interest for to the local society.What are the roles of academics, NGO members and other humanitarian workers on the field of development? What are the perceptions of local people vis-à-vis these different actors?Based on the observations with actors of local and Japanese NGOs, and also with some scholars and experts in Senegal, this paper attempts to highlight the methodological, epistemological and ethical problems to understand the complex relationships between the fields of academic research and humanitarian actions.