The Country Cooperation Strategy is the World Health Organization’s corporate framework developed in response to a country’s needs and priorities. The 2022–2025 CCS is the fourth for WHO in Sierra Leone. It is a medium-term strategic document that defines a broad framework for WHO’s work, at all levels, with the Government of Sierra Leone and all health partners for the next four years. This document is guided by the country’s major policy and strategy documents including the 2020 National Health and Sanitation Policy (NHSP); the 2021–2025 National Health Sector Strategic Plan (NHSSP); and the 2019–2023 National Medium-term Development Plan (NMTDP). The current CCS also reflects the broad priorities of WHO as outlined in its Thirteenth General Programme of Work (2019–2023, extended to 2025) with a focus on improving access to universal health coverage, protecting people from health emergencies, and improving people’s health and well-being. The CCS priorities are also in alignment with the United Nations Sustainable Development Cooperation Framework (UNSDCF) in Sierra Leone and will contribute to attaining the country's SDG targets