Francisco Javier Candel, Marina Peñuelas Department of Clinical Microbiology and Infectious Diseases, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), Universidad Complutense, Madrid, Spain Abstract: Delafloxacin (DLX) is a new fluoroquinolone pending approval, which has shown a good in vitro and in vivo activity against major pathogens associated with skin and soft tissue infections and community-acquired respiratory tract infections. DLX also shows good activity against a broad spectrum of microorganisms, including those resistant to other fluoroquinolones, as methicillin-resistant Staphylococcus aureus. Its pharmacokinetic properties and excellent activity in acidic environments make DLX an alternative in the treatment of these and other infections. In this manuscript, a detailed analysis of this new fluoroquinolone is performed, from its chemical structure to its in vivo activity in recently published clinical trials. Its possible place in the current antimicrobial outlook and in other infectious models is also discussed. Keywords: Delafloxacin, fluoroquinolones, methicillin-resistant Staphylococcus aureus, therapy