This issue of Critical Care Clinics by Dr. Anand Kumar will feature articles on: Optimizing Antimicrobial Therapy in Life-threatening infection, sepsis and septic shock;General principles of antimicrobial dosing and PK/PD; Pharmacokinetic and pharmacodynamic issues in the critically ill with severe sepsis and septic shock;Understanding antimicrobial resistance;Combination vs monotherapy in critical illness; Antifungal therapy.