To support the implementation of the IWRM-Indonesia process in a water scarce and sanitation poor region of Central Java (Indonesia), sustainability assessments of several technology options of water supply and sanitation were carried out based on the conceptual framework of the integrative sustainability concept of the German Helmholtz association. In the case of water supply, the assessment was based on the life-cycle analysis and life-cycle-costing approach. In the sanitation sector, the focus was set on developing an analytical tool to improve planning procedures in the area of investigation, which can be applied in general to developing and newly emerging countries. Because sanitation systems in particular can be regarded as socio-technical systems, their permanent operability is closely related to cultural or religious preferences which influence acceptability. Therefore, the design of the tool and the assessment of sanitation technologies took into account the views of relevant stakeholders. The key results of the analyses are presented in this article.