Historically, career was understood to be a static, linear concept concerned primarily with paid employment. More recently, broader conceptualisations of career have extended its meaning to incorporate all aspects and roles of an individual's life and to acknowledge its inherently complex, individual, dynamic and contextual nature. Change, now recognised as a key characteristic of career, underpins choice-making processes, which are influenced by a range of factors, including broad contextual issues like labour market trends, in addition to more personal concerns such as family circumstances. This thesis explored the career trajectories of early career professionals (ECPs) employed in the Health Care and Social Assistance (HCSA) industry. Specifically, the aims of the study were to investigate how ECPs describe their career trajectories and account for their careerrelated choices, to identify important attractors and deterrents in relation to career-related choices, and to explore the relevance and usefulness of chaos theory to this topic.In particular, the author sought to understand how the career trajectories of ECPs develop in the context of complex systems including the family, organisations and the broader society. The conceptual approach chosen for its potential to capture this complexity was chaos theory. Three principles of chaos theory were explored. First, chaotic systems change with time and are characterised by randomness and variation. Second, they are sensitive to initial conditions. Finally, their functioning and level of change is affected by several types of attractors.The context of this study was Queensland's non-government mental health sector (NGMHS).Challenges currently facing the broader mental health sector include inadequate responses to consumer needs, difficulties in recruiting and retaining skilled mental health professionals, an ageing workforce, and increasing reliance on non-government organisations (NGOs). Early career professionals employed within Queensland's NGMHS were chosen as the subjects of this study for their documented characteristics, which include high career mobility, variable work readiness, overand under-qualifications, and disparities between their expectations and the realities of employment.Their potential to both exacerbate and to counter challenges faced by Queensland's NGMHS made focusing on these ECPs compelling. Recent calls for Australia to enhance its long-term economic sustainability in the global context by concentrating more on developing the service economy, rather than the commodities sector, provided added impetus for this study.A qualitative, exploratory methodology was adopted. The research design involved a two-phase study consisting of concept maps and individual autobiographical interviews. Participants comprised 25Page 2 of 309 ECPs who had completed university studies in the five years prior to 2012 and who were employed in Queensland's NGMHS. Data were analysed thematically, using both inductive and deductive approaches.Early career ...