This document summarizes Indonesia's Water Resources Law of 2004 and discusses some key aspects of water rights and water markets. The 3-sentence summary is: The document outlines Indonesia's Water Resources Law which regulates surface water, groundwater, and other water sources. It discusses the country's agency-based water rights system and some pilot projects exploring a transition to a more market-based approach. Several challenges of incorporating water markets are also mentioned, such as how to account for water's public good attributes and externalities like environmental and social costs.