This review aims to synthesise the literature examining the psychosocial variables related to self-management (insulin adherence, non-adherence and administration, blood sugar monitoring, dietary behaviour, exercise behaviour) in adolescents with type 1 diabetes.A systematic search of three electronic databases was carried out and, after the application of eligibility criteria, 21 articles were assessed for quality prior to data extraction. Numerous psychological factors were found to be associated with self-management; however, correlations were typically small to moderate. The strongest associations were found between social anxiety and diet (among males); greater intrinsic motivation, conscientiousness and diet; and extraversion and exercise. Keywords:Diabetes; adolescence; adherence; diet; exercise behaviour Running head: Psychological factors and adolescent diabetes 3 Type 1 diabetes is a common chronic illness affecting young people in the UK, and its incidence is increasing (Patterson et al., 2012). Although the importance of good glycaemic control to prevent vascular complications (such as retinopathy, neuropathy, and nephropathy) is well recognised, currently in the UK fewer than 25% of children and young adults achieve the target for long-term glycaemic control (HbA1c < 7.5 without frequent hypoglycaemia) (Health & Social Care Information Centre, 2013). Given the plethora of short and long term physical health difficulties related to Type 1 diabetes, it is crucial that young people learn to manage their diabetes effectively, as any decrease in HbA1c decreases the risk of complications (Lind et al., 2009).However, diabetes management in the adolescent age group presents a more complex set of challenges given the range of physiological, social and emotional changes which occur between childhood and adulthood, including puberty, peer pressure, a desire to be "normal", identity formation and, often, testing of boundaries set by healthcare professionals, parents and caregivers .Interventions have focused on enabling young people to better manage their condition. Historically, this has taken the form of educational programmes aimed at teaching specific diabetes management skills and fostering independence with these tasks (for example, carbohydrate counting, blood glucose monitoring), or psychosocial interventions aiming to address self-care and emotional difficulties through a variety of problem-solving and emotion-focused techniques (Peyrot & Rubin, 2007).In 2000, the UK National Health Service Health Technology Assessment programme published a systematic review of the literature on the effectiveness of psychosocial and educational interventions for adolescents with diabetes . The review described small to medium-sized beneficial effects on diabetes management outcomes, but highlighted numerous weaknesses within the literature -more than half the studies (55%) had Running head: Psychological factors and adolescent diabetes 4 no theoretical basis underlying the intervention. A subsequent review (Mur...