Sustainable water resources management is essential since it ensures the integration of social,\u00a0economical and environmental issues into all stages of water resources management. The\u00a0development and application of water sustainability indices to achieve sustainable water\u00a0management has been successfully done in the last few years. Although existing water\u00a0sustainability indices have successfully provided information on current conditions of water\u00a0resources and prioritised water related issues, they have been developed for specific case study\u00a0areas. This study therefore aims at developing a water sustainability index for West Java,\u00a0Indonesia. The overall steps for developing the index include developing a conceptual framework,\u00a0application of Delphi technique to finalise the components\/indicators of the index, applying the\u00a0index to case studies and robustness analysis of the index. This paper, which is the first in\u00a0a two-part series, discusses the first step, namely developing the conceptual framework of the\u00a0West Java Water Sustainability Index (WJWSI). It outlines the criteria for identifying the initial\u00a0set of components\/indicators and based on those criteria, a detailed justification for selecting\u00a0each component and indicator is also presented. The second paper of the series presents the\u00a0application of Delphi technique to finalise the framework of WJWSI based on feedback from\u00a0selected stakeholders. The remaining steps of developing WJWSI will be undertaken in the future.<\/p>\n