Athlete burnout is associated with serious negative consequences, including sport dropout, depression and ill-health, and athletes are experiencing burnout at a higher rate than ever before. However, existing research has failed to reach a consensus on the key predictors of burnout; there is no singular theory of burnout, while longitudinal research and critical comparison between existing perspectives is lacking. As such, the overarching aim of this thesis was to identify key risk and protective factors for development of burnout in Gaelic games, team sports native to Ireland. A systematic review of factors linked to burnout in team-sport athletes informed the development of a longitudinal, quantitative study, wherein burnout and potential predictors were assessed at six timepoints over 21 months. Cross-sectional structural equation models examining stress-, motivation- and commitment-based perspectives of burnout, and exploration of demographic characteristics, identified key factors associated with the dimensions of burnout. Latent growth analyses indicated that feelings of exhaustion became less frequent over time, while feelings of sport devaluation increased and feelings of accomplishment remained relatively stable. Predictors identified through the cross-sectional analyses and systemic review were incorporated into these models to assess their utility in explaining inter-individual variability in initial burnout and rate of change over time, in the first such integrated approach. Findings indicated that factors associated with stress (e.g. training demands), motivation (e.g. amotivation) and commitment (e.g. constrained commitment), as well as demographic characteristics (e.g. playing level), predicted initial burnout and change over time, with different predictors identified across burnout dimensions. As such, results provide important and novel insight into the key risk and protective factors for the development of burnout in Gaelic games, which can inform targeted intervention methods. Furthermore, findings provide empirical support for an integrated approach to the study of burnout, and provide a framework that may inform future research.