Medication safety incidents, adverse drug events (ADEs), and medication errors are synonymous. They are common causes of patient harm worldwide.[1,2] A practical definition of a medication error is “a preventable event that can result in patient harm, while the medication is controlled by a healthcare professional or consumer.”[1] These errors can happen at any point in the medication use process (i.e., from prescription to administration).A sentinel event is an incident that causes severe temporary harm requiring intervention to sustain life, permanent harm, or death.[3] Increasing medication usage and the complex pharmacodynamic effects of novel drugs are intensifying the risk of harm from ADEs. Yet, there is no consensus on the definition of medication errors or on the methods to detect them.[2] Thus, the true incidence of medication errors is unknown.Medication errors are preventable; their reduction is critical to patient safety. Thus, healthcare facilities must have organizational clarity on how to respond to an ADE. The immediate response should focus on minimizing the consequences to the afflicted. Thereafter, the causes must be identified so that sustainable systems-based strategies to reduce the risk of the recurrence of the error can be successfully formulated and implemented.Many of the regulatory bodies for healthcare facilities mandate systematic and comprehensive analysis of sentinel events.[3] Within the healthcare setting, root cause analysis (RCA) is the framework that is most commonly used for such investigations.[3,4]RCA is a structured error analysis tool. It can often identify the system failures and human factors that contributed to an error.[3] Human factors that cause ADEs include lack of knowledge about medications used, inadequate patient information, policy violations, and transcription errors.[5] The system failures that often cause medication errors include issues related to workplace design, complex workflows for medication use, and organizational policies that inadvertently predispose organizations to ADEs.[5]However, despite significant efforts to increase patient safety, and the widespread uptake of RCA, adverse event rates remain essentially unchanged.[6] So, recognizing the limitations of RCA, the National Patient Safety Foundation released a report titled, “RCA2: Improving Root Cause Analyses and Actions to Prevent Harm.”[4] Notably, the process was renamed “Root Cause Analysis and Action (RCA2),” emphasizing that the outcome of error analysis (i.e., corrective actions and risk mitigation) are as important as the process itself.[4]Rather than looking at singular root cause, RCA2 can help us to:We used an abbreviated RCA2 methodology to investigate medication errors that caused harm, but were not sentinel events.[7] We analyzed seven ADEs at our institution in 2018.[7] The investigations identified 39 system failures and initiated several interventions to improve patient safety.[7] Although some similar events reoccurred despite quality improvement initiatives, the recurrence of similar events was significantly reduced, and harm from similar ADEs was eliminated.[7] Furthermore, the interventions made as a result of the abbreviated RCA2 may have prevented other ADEs.[7]Any medication safety incident can be investigated using RCA2. However, performing a full RCA2 consumes significant resources, labor, and time. Thus, most organizations reserve a full RCA2 for medication errors that cause sentinel events.[7] We recommend the use of an abbreviated RCA2 process for the investigation of ADEs that cause harm but are not sentinel events,[7] and frequently occurring ADEs that have not yet caused any harm.After identifying the consequences of the ADE and the associated harm, an RCA2 must answer the following questions:To answer these questions, the steps below must be followed.Step 1: Investigate. Collect the data required to understand the incident by nonjudgmentally questioning the staff involved.Step 2: Identify possible causal and contributing factors. There are almost always several root causes. Do not focus on a single cause. The root causes and the contributing factors must then be categorized. Tools that facilitate this include fishbone diagrams (see Supplemental Figure, available online), cause and effect tools, and the like.Examples of suitable categories for contributing factors include the following:Step 3: Consider how to prevent the recurrence of the incident. Do not try to reinvent the wheel. A literature review can determine whether the responses to any similar ADEs have been described previously.Step 4: Organize meetings with stakeholders to discuss what happened, how and why it happened, and what actions can be implemented to prevent the recurrence of similar events.Step 5: Document the outcomes of meetings and any recommended actions.Step 6: Communicate the recommended actions to all stakeholders for implementation.Step 7: Measure and validate all implemented actions.Step 8: Consider publication of your experience if it is of national or international interest.Using RCA2 to investigate medication errors may reduce their recurrence and thereby improve patient safety. Although the cost associated with RCA2 is not insignificant, the benefits to the healthcare systems may be far greater. To prevent a second victim of the incident, it is important to be compassionate to all the healthcare professionals involved in this process.Supplemental material is available online with the article.