Meropenem is the second carbapenem antibiotic available in the United States. It has a broad spectrum of activity that includes moderate activity against gram-positive bacteria and excellent gram-negative aerobic and anaerobic activity. Meropenem has enhanced gram-negative activity relative to imipenem-cilastatin and often retains activity against strains resistant to third-generation cephalosporins and imipenem-cilastatin. The drug penetrates well into most body fluids and tissues, including cerebrospinal fluid. It is also stable against renal dehydropeptidase hydrolysis and does not require coadministration of a dehydropeptidase inhibitor. Meropenem showed excellent efficacy in clinical studies involving seriously ill patients with intraabdominal, central nervous system, lower respiratory tract, skin and soft tissue, urinary tract, and febrile neutropenic infections. It appears well tolerated and, relative to imipenem-cilastatin, may have reduced potential for causing seizures and other central nervous system toxicities. Although it has many favorable qualities and some potential advantages relative to other broad-spectrum agents, additional trials and clinical experience are necessary to define its optimal place in clinical practice.