A wearable medical system includes a wearable defibrillator device. The device includes a water-resistant/waterproof harness to be continuously or nearly continuously worn by a patient； a plurality of ECG sensing electrodes configured to monitor an ECG of the patient； a plurality of therapy electrodes configured to deliver one or more therapeutic pulses of energy to the patient； and a control unit configured to receive the monitored ECG of the patient, and responsive to the detection of a cardiac arrhythmia, provide the one or more therapeutic pulses to the patient via at least one of the plurality of therapy electrodes if the patient does not indicate that the patient is conscious. The system includes a hand-held user interface device configured to wirelessly communicate with the control unit； the interface device includes at least one patient responsiveness button by which the patient can indicate that the patient is conscious.
