Sanitation should be made accessible to everyone. It is fundamental for our dignity and privacy. As centralized government has been observed to be limited in addressing complex problems, many developing countries resorted to decentralization. In theory, decentralization can improve the provision of public goods and services, including sanitation. Social and political factors are believed to be the leading cause of limiting the progress in the sanitation sector. Multiple studies have demonstrated the importance of social networks in sanitation governance. We propose to further explore interaction between actors based on key activities in sanitation sectors. We choose Jakarta, Indonesia, as our case study. Jakarta, the capital city of Indonesia, is inhabited by 10.56 million people (measured in September 2020). It is estimated that 86% of the population have not received access to properly managed domestic wastewater. The main research question to be answered is “How do the interactions among various actors influence sanitation service provision in Jakarta?”. This thesis explores the influence of multiple key activities to contextualize the current provision of sanitation services in Jakarta, Indonesia. We use the Network of Adjacent Action Situations (NAAS) framework proposed by McGinnis (2011). To identify the action situations, we use the sanitation service delivery function categories used by Mason et al. (2020). The sanitation service systems encompass the provision of related infrastructure, namely sewer network, septic tank, vacuum truck, sewage treatment plant, and fecal sludge treatment plants. Constitutionally, the provision of sanitation services in Indonesia are carried out by provincial and district governments. The provision started to be mandated by minimum public good and service standards in 2014. There is no sanitation law, nor it is integrated with the latest water resource law. Sanitation policies are mainly initiated on the national level. They largely came from four actors: (1) Ministry of Public Works and Housing, (2) Ministry of Health, (3) Ministry of Environment and Forestry, and (4) National Sanitation Working Group which comprise aforementioned ministries and other ministries. These three aforementioned ministries are the most active for sanitation service provision in the national stakeholders. In the subnational government, Jakarta Province, PD PAL Jaya is the technical operator of major sanitation infrastructures in Jakarta. The DKIJ Water Resource Agency is the counterpart of PD PAL Jaya in terms of sanitation service development. The development is additionally influenced by the DKIJ Regional Development Planning Agency, the governor, and the Governor Advisory Team. The DKIJ Environmental Agency is the enforcer of the wastewater standard. This thesis presents seven action situations (AS) constituting the NAAS of Jakarta’s sanitation service intended to describe the current sanitation governance: the National Policy AS, the Jakarta Policy AS, the National Regulation AS, the Jakarta Regulation AS, the National Financing AS, the Jakarta Financing AS, and the Jakarta Production & Provision AS. We found two leverage points where the outcome could cascade over to most other action situations. These are Jakarta Policy AS, which is mostly about planning, and the Jakarta Production & Provision AS which is concerned with implementation.