Dr. Amal Mattu and his colleagues from the University of Virginia, the University of California San Francisco, and Oregon Health & Sciences University, have back-to-back electrocardiographic case reports in the December issue of Annals of Emergency Medicine. The first article (68:671-3) describes the assessment of a woman with Wolff-Parkinson-White syndrome, who came to the emergency department when she experienced palpitations and weakness. The second report (68:674-7) describes a woman with hypertension and diabetes mellitus, who sought emergency treatment for chest pain, nausea, dyspnea, and diaphoresis. This column in Annals starts with a description of patients’ presentations, including the ECG, and asks the reader to reach a diagnosis before reading the experts’ analysis.