Each year, 11.8 million adolescents in the United States cope with a chronic condition (CC), yet much of the research about these youth has been framed from a deficit perspective. The author developed and validated a measure of Positive Youth Development (PYD) for use with adolescents with CCs to address their unique circumstances. Expert ratings reduced 51 items selected from the Connecting Adolescents Beliefs and Behaviors survey to 16 items. Two exploratory factor analyses using orthogonal and oblique rotations further reduced the number of items to 12. Three factors emerged: PYD-Connections to Peers and Schools ([alpha] = 0.81), PYD-Connection to Family ([alpha] = 0.82), and PYD-Confidence ([alpha] = 0.89). Relations between these constructs and perceived health were assessed in healthy youth and youth with CCs. Youth with CCs reported feeling less healthy and worrying more about their health, and endorsed greater levels of feeling depressed. Compared with a matched sample of youth without CCs, youth with CCs had significantly higher correlations between both PYD-Confidence and composite PYD, and degree of health worry and feeling depressed, as well as between connection to peers and school and feeling depressed. The findings highlight the need for a measure of PYD specifically for adolescents with CCs.