Indonesia Climate and Growth Dialog (ICGD) argues that Indonesia can build a strategic carbon market system that supports decarbonisation, attracts large-scale finance, and enhances trade competitiveness. This paper proposes principles to align domestic compliance, international compliance, and voluntary markets so they operate synergistically and encourage high-integrity low-carbon investments. Developed through engagement with government and international partners, the recommendations stress coordinated market design to avoid fragmentation and maintain investor confidence. The framework also clarifies key concepts—high-integrity mitigation activities, development risks, and full project costs—to ensure credible emissions reduction outcomes.