"Compared with other young adults, university students exhibit more mental health problems, and consequent service needs. However, like other young adults, they are reluctant to use available targeted services such as student counselling. There is evidence to suggest that delayed treatment can not only impact academic performance but also students' social and cognitive outcomes later in life. As a precursor to interventions aimed at increasing university students' use of mental health services and improving their mental health, research is needed to elucidate the influential factors in the help-seeking process. The two most widely used theories in this area, respectively predicting intention to use services and actual service use, are the Theory of Planned Behavior and the Behavioral Model of Health Services Use. The Theory of Planned Behavior asserts that intention is an immediate determinant of behaviour. As such, researchers have endeavoured to investigate the factors associated with help-seeking intentions in order to enrich understanding of university students' use of mental health services. However, published findings have been inconsistent. To consolidate the literature on help-seeking intentions, a meta-analytic review (Study 1) investigated the psychosocial correlates of university students' intentions to seek professional mental health care. Eighteen eligible studies with 6,839 participants were identified through a comprehensive search of nine electronic databases. The results indicated that attitudes toward seeking professional help and anticipated benefits had the strongest relationships with students' help-seeking intentions, whereas Asian cultural values, public stigma, and anticipated risks demonstrated small correlations with intentions. No significant relationships were observed between help-seeking intentions and social support, self-disclosure, self-concealment or psychological distress. However, because the relationship between intention and actual behaviour is not clear-cut, predictors of students' intentions to seek mental health care may not have impact on their actual use of mental health services. Accordingly, some researchers have employed the Behavioral Model of Health Services Use - a key theoretical framework for explaining and understanding individuals' healthcare use - to examine direct predictors of young adults' or university students' actual service use. Conflicting findings have again emerged. In Study 2, a systematic review with effect sizes, the associations between different biopsychosocial variables (e.g., gender, social support and psychological distress) and young adults' use of mental health services were formally combined and evaluated. Although the initial focus of this systematic review (as for the overall project) was on university students, preliminary searches revealed few published correlational studies of university students' service usage. The sampling criteria were therefore widened to specify young adults (a category to which most university students belong). Eighteen eligible studies, resulting in a total of 96,297 participants, were identified through systematic searches of nine electronic databases. The findings, in combination, identified that prior service use, gender, ethnic background, and sexual orientation, together with evaluated and perceived need for professional help, were significant predisposing and need variables associated with young adults' actual service use. The results of Studies 1 and 2 were largely based on help-seeking research that had been conducted in the United States, highlighting a need to explore help-seeking intentions and the use of mental health services among domestic university students from different countries and cultural backgrounds. Moreover, integrated models were needed to examine and explain the interactions between identified predictor variables, help-seeking intentions, and actual service usage. These research needs were addressed in Studies 3 and 4, which utilised structural equation modelling and logistic regression analyses to assess the impact of different biopsychosocial variables on mainland Chinese and Australian domestic university students' help-seeking intentions and their use of mental health services. For Study 3, a sample of 1,128 mainland Chinese university students (mean age = 20 years; SD = 1.48) was recruited: 630 males and 498 females completed an online survey comprising standardised psychometric measures in Mandarin. The proposed model of help-seeking intentions, which integrated the Theory of Planned Behavior and the Behavioral Model of Health Services Use, exhibited a good fit to the study data. Attitudes, subjective norms, and perceived behavioural control significantly mediated the relationships between gender, Asian cultural values, social support, evaluated need, anticipated benefits, anticipated risks, public stigma, self-stigma and help-seeking intentions. Actual service usage in the preceding 12 months was significantly predicted by help-seeking intentions, perceived behavioural control, frequency of exposure to mental health service related information, self-rated mental health status, and perceived need for help. In Study 4, a similar online survey was completed in English by 611 Australian domestic university students (209 males and 402 females; mean age = 21 years, SD = 5.6). This study built on Study 3, by developing and testing four help-seeking models, and found that the model proposed and tested in Study 3 also resulted in the best fit for the Australian data. Attitudes and subjective norms significantly mediated the effects of knowledge of mental health and services, Asian cultural values, evaluated and perceived need, anticipated benefits, public stigma, and self-stigma on Australian students' help-seeking intentions. Significant predictors of service use included help-seeking intentions, perceived behavioural control, gender, study major, knowledge of mental health, Asian cultural values, social support, income, self-rated mental health status, and perceived need. In combination, these four empirical studies have addressed key gaps in the research literature regarding university students' mental health help-seeking. Moreover, Studies 3 and 4 make an important contribution to current knowledge concerning formal help-seeking behaviour and intentions by mainland Chinese and Australian domestic university students. There are a number of implications for theory and future research directions in addition to practice by education providers, mental health professionals and policy makers. From a theoretical perspective, the project provides empirical support for the applicability of both the Theory of Planned Behavior and the Behavioral Model of Health Services Use to understanding university students' mental health help-seeking. From a practical standpoint, the findings suggest that to stimulate mental health service use, education providers and mental health professionals should consider psycho-educational and marketing campaigns, to enhance understanding of mental health disorders and services among university students, their families and friends, in addition to reducing stigma concerns and normalising service use within this vulnerable population. Future longitudinal research will be helpful to extend the current findings by examining causal relationships between the identified biopsychosocial variables, university students' help-seeking intentions, and their actual use of mental health services." -- abstract, pages iv-vii.