OBJECTIVE: This study assessed health-related quality of life (HRQOL) and treatment satisfaction in sensor-augmented pump therapy (SAPT) compared with optimal conventional therapy-multiple daily injection (MDI) therapy with self-monitoring of blood glucose (SMBG)-in adults and children with type 1 diabetes and children's caregivers. Patient acceptance of new therapies is essential to their adoption and effective use. RESEARCH DESIGN AND METHODS: STAR 3, a randomized 12-month clinical trial, compared SAPT with MDI+SMBG in 485 adult and pediatric patients. Within- and between-treatment arm changes in generic HRQOL, diabetes-specific HRQOL (fear of hypoglycemia), and treatment satisfaction were assessed (significance criterion P<0.01). RESULTS: In adults, children, and caregivers, there were no significant between-arm changes in generic HRQOL: SF-36 Physical Component Summary and Mental Component Summary scores in adults and the PedsQL Physical Health Summary and Psychosocial Health Summary scores in children or caregivers. Diabetes-specific HRQOL (Hypoglycemia Fear Survey Worry and Behavior subscale scores) improved more in SAPT than in MDI adults. Hypoglycemia Behavior scores improved more in SAPT caregivers. Key treatment satisfaction measures (Insulin Delivery System Rating Questionnaire measures of Convenience, Efficacy, and Overall Preference) improved more in SAPT adults, children, and caregivers (all P<0.001); all exceeded the criterion for minimal detectable difference. CONCLUSIONS: In the first-ever large-scale study of SAPT compared with optimal conventional therapy, SAPT had significant advantages for hypoglycemia fear in adults and caregivers and for treatment satisfaction in adults, children, and caregivers.