To evaluate unattended full polysomnography (PSG) recorded in the home by the DigiTrace Home Sleep System (DHSS) and to assess the ability to acquire, store and analyze polysomnographic data using the DHSS compared to standard paper PSG. Part 1 used a prospective, cross-over design. Part 2 consisted of a prospective concurrent collection of polysomnographic data. Sleep Disorders Center in a university medical center. All adult patients who required standard clinical PSG as part of their clinical evaluation, regardless of suspected diagnosis, except patients requiring video recording for abnormal behaviors. The DHSS is a digital recording system with miniature preamplifiers and the capacity to record 18 channels of polysomnographic data, including 4 channels of EEG (C3-A2, C4-A1, C3-O1 and C4-O2), right and left EOG, two channels of chin EMG, ECG naso-oral airflow, respiratory effort (piezo crystal thoracic and abdominal belts and bilateral intercostal EMG), snore microphone, bilateral anterior tibialis EMG, and body-position sensor. In part 1, 77 DHSS home recordings were evaluated. No recordings were lost due to equipment failure and each parameter was scorable in greater than 95% of all epochs. Most of the subjective assessments by questionnaire following each study revealed no difference between the two testing situations. However, patients reported more sleep time and a better overall test experience in the lab. Assessments of sleep quality and morning alertness compared to usual were rated higher in the lab. After completing both studies, more patients preferred the lab study (p<.01), mostly because of minor inconveniences and apprehension regarding acquisition of data during the home study. There was no difference in the assessment of which test most accurately represented their sleep. In part 2, the DHSS recorded concurrently with paper PSG in the laboratory in 16 patients. The results show no significant differences for any parameter and strong positive correlations for all parameters. Using the DHSS, unattended full PSG can be performed in the home with reliable and high quality recordings. Full PSG can be extended to a larger patient population, because it is no longer limited by the number of beds, and there is a reduction in cost due to elimination of overnight staff and facility cost.