Although technology has helped decrease medication errors, adverse drug events remain a significant source of harm. Patients in the intensive care unit (ICU) may be particularly vulnerable to medication errors due to the complex nature of their care. Prior research has shown that medication errors occur more frequently in the ICU and are more likely to cause serious patient harm or death. This clinical practice guideline highlights environmental changes and prevention strategies that can be employed to improve medication safety in the ICU. The authors also describe components of active surveillance that may augment detection of medication errors and adverse drug events. A previous WebM&M commentary discussed a case involving a serious medication error in the ICU setting.