Deforestation in Indonesia is a crisis of global dimensions. It has attracted worldwide attention in recent years, particularly due to forest fires leading to a transboundary haze crisis and the pressure of palm oil plantations causing the loss of habitat and biodiversity. While previous studies tend to focus on the drivers of deforestation, they fail to understand why there is no general consensus on the actual extent of deforestation in Indonesia. This thesis seeks to analyze the major data sources for the deforestation rate in Indonesia and to understand why their numbers differ from each other. Drawing on existing literature and expert interviews, the thesis analyzes five different sources in more detail: The Indonesian Ministry of Environment and Forestry (MoEF), the United Nations Food and Agriculture Organization (FAO), the Global Forest Watch (GFW) using the data from Hansen et al. (2013), Margono et al. (2014) and Gaveau et al. (2016). The findings indicate that there are four major factors causing the discrepancies in data: interests / purpose of existence of the respective source, definitions of forest area and changes, methodology, and other factors particularly concerning governance issues in the Indonesian context. The findings of this study suggest that particularly different interests have a strong influence on applied definitions and methodologies, and subsequently on the reported rates of forest loss. This thesis argues that due to different interests, which are often rooted in the purposes of existence and longstanding values of the institutions, discrepancies in data exist and will continue to persist in the future. Therefore, this thesis recommends that the interests of the reporting organization have to align with the interests for which the data are used in order to meet stated objectives. Furthermore, it provides a framework for potential fields of application of the data from the examined sources.