The Self-care of Diabetes Inventory (SCODI or “Scotty”) was developed by a team in Italy based on the Self-care of Chronic Illness theory. They developed 40 SCODI items (5 points Likert type) based on clinical recommendations and grouped them into 4 dimensions: self-care maintenance, self-care monitoring, self-care management and self-care confidence based on the theory. Content validity was assessed by a multidisciplinary panel of experts. They then conducted a multi-centre study of adults with type 1 or type 2 diabetes. In those analyses (currently under review), reliability and validity were demonstrated. Content validity ratio was 100%. The inventory structure was multidimensional with 4 scales, all of which were reliable: Multidimensional model-based reliabilities were between 0.81 (maintenance) and 0.89 (confidence). Significant associations were found between self-care and the outcomes of HbA1c and complications of diabetes. We advocate the SCODI is a valid and reliable theoretically-grounded tool to measure self-care in type 1 and type 2 DM patients.