BACKGROUND: Tuberculosis (TB) strains with drug resistance (DR-TB) are more difficult to treat than drug-susceptible ones, and threaten global progress towards the targets set by the End TB Strategy of the World Health Organization (WHO). WHO estimates that about half a million cases of multi-drug or rifampicin resistant (MDR/RR-TB) are estimated to occur each year. However, only one third were estimated to have accessed effective treatment and of those, just over half had a successful treatment outcome. Therefore, there is a pressing need for evidence-based policy recommendations on the treatment and care of patients with DR-TB, based on the most recent and comprehensive evidence available. In this regard, the WHO Consolidated Guidelines on Tuberculosis, Module 4: Treatment - Drug-Resistant Tuberculosis Treatment fulfills the mandate of WHO to inform health care professionals in Member States on how to improve treatment and care for patients with DR-TB. The 2020 recommendations on drug resistant TB treatment are contained in the second module to be released under the rubric of WHO Consolidated Guidelines on Tuberculosis (Module 4: Treatment). The WHO Consolidated Guidelines on Tuberculosis will group all TB recommendations in one document and will be complemented by matching modules of a consolidated operational handbook. The operational handbook will provide practical advice on how to put in place the recommendations at the scale needed to achieve national and global impact. OVERVIEW: Between 2011 and 2019, WHO has developed and issued evidence-based policy recommendations on the treatment and care of patients with DR-TB. These policy recommendations have been presented in several WHO documents and their associated annexes, including the WHO Consolidated Guidelines on Drug Resistant Tuberculosis Treatment, issued by WHO in March 2019. The policy recommendations in each of these guidelines have been developed by WHO-convened Guideline Development Groups, using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach to summarize the evidence, and formulate policy recommendations and accompanying remarks. The present WHO Consolidated Guidelines on Tuberculosis, Module 4: Treatment - Drug-Resistant Tuberculosis Treatment includes a comprehensive set of WHO recommendations for the treatment and care of DR-TB. The document includes two new recommendations, one on the composition of shorter regimens and one on the use of the BPaL regimen (i.e. bedaquiline, pretomanid and linezolid). In addition, the consolidated guidelines include existing recommendations on treatment regimens for isoniazid-resistant TB and MDR/RR-TB, including longer regimens, culture monitoring of patients on treatment, the timing of antiretroviral therapy (ART) in MDR/RR-TB patients infected with the human immunodeficiency virus (HIV), the use of surgery for patients receiving MDR-TB treatment, and optimal models of patient support and care. The guidelines are to be used primarily in national TB programmes, or their equivalents in Ministries of Health, and for other policy-makers and technical organizations working on TB and infectious diseases in public and private sectors and in the community.