The emergence of multi-drug resistant Acinetobacter spp involved in hospital-acquired infections, once considered an easily treatable pathogen, is troublesome and an immense burden for the modern medical systems worldwide. In the last 20 years the medical community recorded an increase in the incidence and severity of these infections as therapeutic means tend to be less and less effective on these strains. The ability of these bacteria to rapidly develop resistance to antimicrobial agents by continuously changing and adapting their mechanisms, their ability to survive for long periods of time in the hospital environment and the multitude of transmission possibilities raises serious issues regarding the management of these complex infections. The future lies in developing new and targeted methods for the early diagnosis of A. baumannii, as well as in the judicious use of antimicrobial drugs. This review details the evolution of the pathogenicity of this microorganism, together with the changes that appeared in resistance mechanisms and the advancements in molecular testing for the early detection of infection.