These are the first WHO guidelines on the screening, care and treatment of persons with HCV infection. They are intended to complement existing guidance on the primary prevention of HCV and other bloodborne viruses by improving blood and injection safety, and health care for people who inject drugs (PWID) and other vulnerable groups, including those living with HIV (see section 2.4 for related WHO guidelines). These guidelines are primarily targeted at policy-makers in ministries of health working in low- and middle-income countries who formulate country-specific treatment guidelines and who plan infectious diseases treatment programs. These guidelines are intended to assist officials as they develop national hepatitis C treatment plans and policy, and guideline documents. In addition, it is anticipated that nongovernmental agencies and health professionals organizing treatment and screening services for hepatitis C will use the guidelines to define the necessary elements of such services. These guidelines will also be a useful resource for clinicians who manage persons with HCV infection. This guidelines document will be revised in 2016. Because a number of new medicines are expected to become available in the meantime, WHO will issue interim guidance twelve months after publication of these guidelines to provide recommendations regarding newly approved medicines.