Abstract
 It is a sociological reality that individual differences exist in society. However, despite all our differences, we see that we have mentalities that show that we do not think very differently from each other in our social life. These mentalities also affect the unique development and progress processes of each society. In our research, from such a point of view, the universe of meaning of the phenomenon of mentality that determines and transforms attitudes and behaviors was revealed and it was evaluated how working in a regional development agency has an effect on the perception of development agency personnel towards the concept of development. This study is the first of its kind in Türkiye since the relationship between development and mentality has not been revealed in a sociological sense until today. The data of the research, which adopts the interpretative sociology method, is limited to the results of in-depth interviews conducted with 45 staff working in the development agency between December 2019 and February 2020. According to the findings obtained in this study, it is understood that the habitus of regional development agencies provides a multidimensional perspective to the agency staff, but the authoritarian mentality elements dominant in the public sector shape the habitus in this field.