Insight into Acinetobacter baumannii: pathogenesis, global resistance, mechanisms of resistance, treatment options, and alternative modalities Muhammad Asif,1,2 Iqbal Ahmad Alvi,1,3 Shafiq Ur Rehman1 1Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore, Pakistan; 2Department of Pathology, King Edward Medical University, Lahore, Pakistan; 3Department of Microbiology, Hazara University, Mansehra, Pakistan Abstract: Acinetobacter baumannii, once considered a low-category pathogen, has emerged as an obstinate infectious agent. The scientific community is paying more attention to this pathogen due to its stubbornness to last resort antimicrobials, including carbapenems, colistin, and tigecycline, its high prevalence of infections in the hospital setting, and significantly increased rate of community-acquired infections by this organism over the past decade. It has given the fear of pre-antibiotic era to the world. To further enhance our understanding about this pathogen, in this review, we discuss its taxonomy, pathogenesis, current treatment options, global resistance rates, mechanisms of its resistance against various groups of antimicrobials, and future therapeutics. Keywords: antibiotic resistance, colistin, tigecycline, phage therapy