ORIGINAL ARTICLE Mental Health among Youth in South Australia: A Survey of Flourishing, Languishing, Struggling, and Floundering Anthony Venning, 1 Anne Wilson, 2 Lisa Kettler, 1 and Jaklin Eliott 3 1 School of Psychology, The University of Adelaide, 2 School of Nursing, The University of Adelaide, and 3 Cancer Council Australia and Discipline of Public Health, School of Population Health & Clinical Practice The Complete State Model of Mental Health was used to describe the prevalence of flourishing, languishing, struggling, and floundering in life in a sample of young South Australians (n = 3,913; 13–17 years, 52% female). Categorisation was based on the relative proportion of mental health and mental illness symptoms reported on standardised measures and the association of these categories to health-risk behaviour. Variability in categories and health-risk behaviour due to gender or region was investigated. Results indicated that a disturbingly small proportion of adolescents (<50%) were flourishing in life, that poorer states of mental health were associated with increased health-risk behaviour, and that the propensity to engage in health-risk behaviour did vary by gender and region. The current study extends the platform from which positively focused mental health strategies can be tailored and launched to meet the mental health needs of adolescents. Key words: adolescents; health promotion; mental health; positive psychology. Mental health is fundamental to well-being, and relates to an individual’s positive emotions, thoughts, and behaviours (Australian Bureau of Statistics [ABS], 1997). Indicated by the presence of positive and the absence of negative symptoms of functioning (Keyes & Lopez, 2002), mental health is defined as a state in which an individual is able to realise his or her own abilities, handle day-to-day events and obstacles, function effec- tively among his or her peers, and engage in health-promoting behaviour (ABS, 1997; World Health Organization, 2005). Alternatively, mental illnesses are among the greatest causes of disability, lost productivity, and diminished quality of life (Australian Health Ministers [AHM], 2003). Mental illnesses are indicated by the absence of positive and the presence of negative symptoms of functioning (Keyes & Lopez, 2002), and are typi- cally associated with distress or impairment in day-to-day func- tioning (American Psychiatric Association, 2000). Adolescence is characterised by immense biological and psychosocial changes (Carr-Gregg, Enderby, & Grover, 2003), and is generally defined as the developmental period between the age of 12 and 20 years (Graber, Brooks-Gunn, & Petersen, 1996; Seifert, Hoffnung, & Hoffnung, 2000). However, while adolescence is a time of increased vulnerability to mental illnesses and/or the adoption of health-risk behaviour that can severely impact future devel- opment (Australian Institute of Health and Welfare [AIHW], 2006a; Rowling, 2006; Rutter & Smith, 1995; Sawyer et al., 2000), it is also a crucial time for the development of mental health and enduring positive health behaviour (Maggs, Schulenberg, & Hurrelmann, 1997). To some degree, risk-taking behaviour during adolescence is normal as individuals attempt to discover and consolidate their identity (Carr-Gregg et al., 2003). However, risk-taking behaviour becomes abnormal when the type or frequency of behaviour has the potential for serious, long-term, and negative health consequences (Irwin, Igra, Eyre, & Millstein, 1997). For example, while not every adolescent who experiments with Correspondence: Anthony Venning, School of Psychology, The University of Adelaide, Adelaide, SA 5000, Australia. email: anthony.venning@ adelaide.edu.au Accepted for publication 8 February 2012 doi:10.1111/j.1742-9544.2012.00068.x What is already known on this topic? 1 Previous research has estimated that up to 86% of young Aus- tralians have good mental health. 2 Adolescence is a critical time for the development of mental health and positive health behaviour. 3 An exclusive focus on mental illness does not promote or lead to mental health. What this article adds? 1 The majority of adolescents sampled were not flourishing in life and engaged in more health-risk behaviour than those who were. 2 A practical approach to assess the mental health of adolescents via the absence of psychological strengths rather than just the presence of mental illness. 3 Extends the platform to launch strategies to meet the mental health needs of young Australians. Australian Psychologist 48 (2013) 299–310 © 2012 The Australian Psychological Society 299