Music thanatology represents an emerging area in which the raw materials of music, usually harp and/or voice, assist and comfort the dying patient. During prescriptive "music vigils, " the clinician-musician carefully observes physiological changes, cues, and breathing patterns, thereby synchronizing the music to reflect or support the patient's physiology and overall condition. Using data collected from 65 patients, this study was designed to assess the effectiveness of prescriptive harp music on selected palliative care outcomes using a sample of de-identified data forms from past music vigils. Patients were administered a 25- to 95-minute intervention of prescriptive harp music. Data collected included vital signs and observational indicators before (Ti) and after (T2) the vigil. Patients were more likely to experience decreased levels of agitation and wakefulness while also breathing more slowly and deeply with less effort at the conclusion of the music vigil. Results from this study suggest that a prescriptive vigil conducted by a trained music thanatologist could provide an effective form of palliative care for dying patients.