Medication errors are preventable events that contribute significantly to patient harm, adverse outcomes, and even death. The cost of medication errors is over $40 billion annually; these errors contribute not only to increased overall healthcare costs but also to decreased patient trust in the healthcare system. In this presentation, various causes of medication errors will be examined, including errors of commission, omission, decision, and excision. High-alert and high-risk drugs will be described, and dangerous drug combinations will be investigated. Further, strategies to reduce errors and mitigate adverse outcomes will be explored.