Digital technologies are making a significant impact on societies, economies, and the physical world, presenting both opportunities and challenges for the green agenda. Applications of these technologies in sectors such as energy, urban, transport, and agriculture are creating new possibilities for climate change mitigation strategies. However, the rapid expansion of digital technologies increases energy usage too, and is therefore also increasing greenhouse gas (GHG) emissions. In seeking to address these challenges, the World Bank's Digital Development Global Practice (DD) will publish a flagship report on Digital Development Opportunities for Climate Change, which will assess opportunities for greening with information communication technology (ICT), as well as opportunities for greening the ICT sector itself. To inspire and inform this flagship report, DD studied Korea's experience in greening its ICT sector, with support from the Korean Green Growth Trust Fund. The Republic of Korea was selected for the case study due to its experience in both the digital and green sectors, and its status as a globally recognized ICT powerhouse. The country was also an early adopter of a green policy agenda, and is integrating DNA (data, network, and AI) into these policies. The government announced a national policy vision of "Low Carbon, Green Growth" in 2008 and has taken concrete steps to build a solid foundation for the green transition, through legislation, standardization, information-based instruments, economic instruments, research and development (R&D), and green procurement. More recently, the country has been aligning its green ICT strategy with the broader national GHG reduction target. Korea's experience can offer meaningful lessons to other countries looking to reduce the ICT sector's climate impact. It shows that public policies have an important impact on the ICT market. The policy tools that can spur decarbonization of the ICT sector include green government procurement, information-based instruments, economic instruments, and provision of guidelines on green business practices. Keys to success in applying such tools include strong and early political commitment; long-term planning and comprehensive policies; prioritization; research and development (R&D) and investment; and a governance structure that allows a whole-of-government approach. Additionally, Korea's experience shows that renewable energy will play an increasingly important role in reducing GHG emissions from the energy-intensive ICT industry. Korea's experience also underscores the fact that more evidence and analysis are needed to measure and determine the effectiveness of policy and regulatory pathways for greening the ICT sector.