Early mobilization of patients in the hospital and the intensive care unit has a strong historical precedent. However, in more recent times, deep sedation and bed rest have been part of routine medical care for many mechanically ventilated patients. A growing body of literature demonstrates that survivors of severe critical illness commonly have significant and prolonged neuromuscular complications that impair their physical function and quality of life after hospital discharge. Bed rest, and its associated mechanisms, may play an important role in the pathogenesis of neuromuscular weakness in critically ill patients. A new approach for managing mechanically ventilated patients includes reducing deep sedation and increasing rehabilitation therapy and mobilization soon after admission to the intensive care unit. Emerging research in this field provides preliminary evidence supporting the safety, feasibility, and potential benefits of early mobilization in critical care medicine.