Research over the past decade has resulted in the development of two commercial interferongamma release assays (IGRAs), based on the principle that the T-cells of individuals who have acquired TB infection respond to re-stimulation with Mycobacterium tuberculosis-specific antigens by secreting interferon gamma (IFN-γ). The QuantiFERON-TB Gold (QFT-G, Cellestis, Australia) and the newer generation QuantiFERON-TB Gold In-Tube (QFT-GIT, Cellestis, Australia) are whole-blood based enzyme-linked immunosorbent assays (ELISAs) measuring the amount of IFN-γ produced in response to three M. tuberculosis antigens (QFT-G:ESAT-6 and CFP-10; QFT-GIT: ESAT-6, CFP-10 and TB7.7). In contrast, the enzyme-linked immunospot (ELISPOT)-based T-SPOT.TB (Oxford Immunotec, UK) measures the number of peripheral mononuclear cells that produce INF-γ after stimulation with ESAT-6 and CFP-10. Commercial IGRAs are FDA-approved as indirect and adjunct tests for TB infection, in conjunction with risk assessment, radiography and other medical and diagnostic evaluations. In recent years, IGRAs have become widely endorsed in high-income countries for diagnosis of latent TB infection (LTBI) and several guidelines (albeit equivocal) on their use have been issued. Currently, there are no guidelines for IGRA use in low- and middle-income countries - typically with high TB- and/or HIVburden - yet IGRAs are being marketed and promoted, especially in the private sector. The majority of IGRA studies have been performed in high-income countries and mere extrapolation to low- and middle-income settings with high background TB infection rates is not appropriate. Systematic reviews have suggested that IGRA performance differs in high- versus low TB and HIV incidence settings, with relatively lower sensitivity in high-burden settings. The WHO Stop TB Department (WHO-STB) therefore commissioned systematic reviews on the use of IGRAs in low- and middle-income countries, in pre-defined target groups, with funding support from the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) and TREAT-TB/The Union. The target groups and major findings of the GRADE evidence synthesis process are summarised below. This Policy Statement applies to the use of commercial IGRAs in low- and middle-income countries only. Several international guidelines on IGRA use in high-income countries are available. This Policy Statement is not intended to apply to high-income countries or to supersede their national guidelines.