Severe sepsis and septic shock remain the leading causes of multiple organ failure and mortality in surgical intensive care units. Early antibiotic therapy recently became a challenge, because of the increased number of infections caused by multiple drug resistant bacteria, with Gram-negative bacteria such as Klebsiella pneumoniae and Pseudomonas aeruginosa being the most frequently cultured pathogens.In this review, detailed recommendations for the treatment of various infections are presented and discussed, with particular emphasis on the determination of empiric antibiotic therapy in the early stages of sepsis and localised infections.