At least one of a medical device, such as an implantable medical device, and a programming device determines values for one or more metrics that indicate the quality of a patient's sleep. Sleep efficiency, sleep latency, and time spent in deeper sleep states are example sleep quality metrics for which values may be determined. In some embodiments, determined sleep quality metric values are associated with a current therapy parameter set. In some embodiments, a programming device presents sleep quality information to a user based on determined sleep quality metric values. A clinician, for example, may use the sleep quality information presented by the programming device to evaluate the effectiveness of therapy delivered to the patient by the medical device, to adjust the therapy delivered by the medical device, or to prescribe a therapy not delivered by the medical device in order to improve the quality of the patient's sleep.