To support WHO member countries in their efforts to strengthen detection of TB disease and infection the current update of the consolidated guidelines on TB diagnosis is being issued. When compared with the third edition (issued in 2024), this guideline is the first to combine the WHO policy guidance on diagnosis of TB infection, disease and drug resistance into a single reference document; also, it establishes two new classes of TB diagnostic technologies (for the initial detection of TB and resistance to rifampicin), and outlines new recommendations on concurrent testing of respiratory and non-respiratory samples among adults and adolescents with HIV, children with HIV, and children without HIV or with unknown HIV status.