The Department for HIV, Tuberculosis, Hepatitis and Sexually Transmitted Infections leads the development of guidelines in the area of HIV, tuberculosis (TB), viral hepatitis and sexually transmitted infections (STIs), as well as guidelines focusing on key aspects of the public health response across the 4 infectious disease areas. 

Recommendations in WHO guidelines are based on sound scientific evidence. Fundamental steps in the process for guideline development include formulating key questions, evidence retrieval and synthesis, and appraisal of the quality of the evidence. But the methods used in these steps were originally conceived for the development of clinical interventions as part of the evidence-based medicine movement.

WHO develops guidelines on a broad array of clinical, public health, health system, health promotion and implementation strategies. These interventions are often highly context-specific, with multiple factors that directly and indirectly impact the health and societal outcomes.