Transitions of care pose a risk to medication safety. To reduce patient harm, medication reconciliation is advised. However, implementation of medication reconciliation is difficult due to time constraints. We present two female patients aged 82 and 84 years. In both women, unintentional discrepancies arose, went undetected and led to patient harm. Accurate information transfer is essential for continuity of patient care. Medication reconciliation comprises four steps, i.e. verification (identify discrepancies), clarification (check the collected list), reconciliation (document the reason for medication changes) and transfer (communicate the updated list). This article discusses the steps of medication reconciliation and those medication errors that arise during a patient's transfer from the home setting to hospitalization or a clinic visit. We show that medication reconciliation is not merely an administrative task. As the patient is the only constant factor in health care, patient participation is essential.