The alarming increase in antibiotic resistance rates reported for various pathogens has resulted in the use of alternative treatment policies. Given the fairly limited availability of new antimicrobial drugs, the reassessment of older antibiotics is now an interesting option. Fosfomycin, a bactericidal analog of phosphoenolpyruvate that has been previously been employed as an oral treatment for uncomplicated urinary tract infection, has recently raised interest among physicians worldwide. In general, the advanced resistance described in Gram-negative bacteria suggests that fosfomycin can be an appropriate treatment option for patients with highly resistant microbial infections. This review, which refers to key available data, focuses on the possibility of extending the use of fosfomycin beyond urinary tract infections and against multidrug-resistant Gram-negative bacteria.