The thesis critically reviews the relationships between anxiety and sports perfonnance, self-confidence and sports perfonnance, and self-efficacy with progress towards life goals. Limitations to previous research are highlighted and alternative theoretical explanations are offered. In subsequent empirical chapters these alternative explanations are tested. The first chapter provides a critical overview of the research area. Limitations are highlighted, and alternative theoretical explanations are presented. Chapter 2 explores the anxiety-performance relationship and provides two empirical studies that suggest that previous findings on the cusp-catastrophe model of anxiety and performance may have been due to a complex interaction between cognitive anxiety and effort required rather than between cognitive anxiety and physiological arousal. Results from both studies provide evidence to support a cognitive explanation for the effects of anxiety upon perfon-nance. Chapter 3 explores the relationship between self-confidence and perfon-nance and addresses the issue that previous research has only considered actual self-confidence (e. g. confidence levels measured within an hour of performance) and has generally ignored the nature of "self' e. g., the "ideal", "ought" and "feared" self-confidence levels that may be used by performers as reference points. Results revealed that discrepancies from these 'selves' significantly predicated 11 % performance variance over and above "actual" measures of self-confidence. Chapter 4 explores limitations in previous research into the effects of self-efficacy on goal progress; namely that this research has tended to focus only upon approach goals. However, research suggests that both goal importance and goal polarity (i. e. approach and avoidance goals) may moderate the effects of self-efficacy on goal progress. Results revealed (amongst other findings) that self-efficacy was significantly correlated with progress on important avoidance life goals but not with progress on important approach goals. The final chapter provides a general discussion of the thesis findings, suggestions for future research and applied implications.