This report establishes the first milestone in a partnership between the Government of Saint Lucia (GoSL), the United Nations Office for Project Services (UNOPS), and the University of Oxford-led Infrastructure Transitions Research Consortium (ITRC). The purpose of the report is to establish a vision for the island’s future infrastructure aligned with the Sustainable Development Goals and the Paris Agreement on climate change. Long-term demand for infrastructure services in Saint Lucia is projected to increase as it pursues economic ambitions to grow its tourism and agriculture sectors. However, at a time of major global disruption caused by the COVID-19 pandemic, uncertainties as to the future of Saint Lucia’s economy are higher than ever before. As an important step in building a sustainable and resilient future, this report equips Saint Lucia with a robust approach to infrastructure planning that can ensure that social, economic, and environmental needs are met in a range of future scenarios. Through extensive data collection and cross-sectoral analysis, this report estimates Saint Lucia’s future infrastructure needs for energy, water, wastewater, and solid waste services and delivers recommendations for how those needs can be met in alignment with national priorities and international development commitments. Additionally, climate change-driven hazards posing risks to economic infrastructures, social infrastructures, natural environment assets, and development projects are assessed for the purpose of prioritizing adaptation measures. In doing so, it provides new and important evidence to support infrastructure decision-making to ensure long-term sustainable and resilient development.