The article discusses the rise of *Enterococcus* as a significant nosocomial pathogen, particularly *Enterococcus faecium*, and the factors contributing to its increasing prevalence and resistance to antibiotics. The authors highlight the impact of antibiotic use on the gut microbiota, which facilitates the colonization and spread of vancomycin-resistant *Enterococcus* (VRE) in hospitalized patients. They also review the genetic and genomic characteristics of *E. faecium*, including the presence of specific clonal lineages that are more adapted to hospital environments. The article further explores the mechanisms of antibiotic resistance in *E. faecium*, such as β-lactamase production, aminoglycoside resistance, and glycopeptide resistance, and discusses the challenges these resistance mechanisms pose to clinical treatment. Finally, the authors emphasize the need for continued research into the biology and genetics of *E. faecium* to develop new strategies for preventing and treating infections caused by this pathogen.The article discusses the rise of *Enterococcus* as a significant nosocomial pathogen, particularly *Enterococcus faecium*, and the factors contributing to its increasing prevalence and resistance to antibiotics. The authors highlight the impact of antibiotic use on the gut microbiota, which facilitates the colonization and spread of vancomycin-resistant *Enterococcus* (VRE) in hospitalized patients. They also review the genetic and genomic characteristics of *E. faecium*, including the presence of specific clonal lineages that are more adapted to hospital environments. The article further explores the mechanisms of antibiotic resistance in *E. faecium*, such as β-lactamase production, aminoglycoside resistance, and glycopeptide resistance, and discusses the challenges these resistance mechanisms pose to clinical treatment. Finally, the authors emphasize the need for continued research into the biology and genetics of *E. faecium* to develop new strategies for preventing and treating infections caused by this pathogen.