This pilot study investigated the impact of freezing of gait, objectively measured with three inertial sensors, on mobility function during seven days of communityliving monitoring in people with Parkinson's disease.Twenty-four subjects with PD, of which 14 experiencing freezing of gait, were recruited in this study. Subjects wore three inertial sensors (Opals, APDM) attached to both feet and the lumbar region for a week of continuous monitoring. Walking bouts, of at least 10s, were first identified, and then features of freezing, quantity and quality of mobility were extracted and averaged across the seven days.Results showed significant impairments in freezing and quality of mobility in the freezers group compared to the nonfreezers. Our measures of average and variability of time spent freezing was associated to the subjects' perception of freezing, assessed with the New Freezing of Gait Questionnaire. These preliminary results are introducing promising measures of mobility impairments measured during community-living in PD.