Background: Common mental health conditions such as depression and anxiety affect 25%- 30% of adults worldwide. Of those experiencing a common mental health condition, only 6%-27% seek or receive any kind of mental health treatment. Traditionally, men are more reluctant to seek help or receive appropriate treatment for mental health conditions contributing to their three times greater risk of suicide. This pattern is most concerning for male students, as suicide is the leading cause of death for 20-34-year-olds, making up 30% of avoidable deaths. Barriers such as mental health stigma, conformity to masculine norms, mental health literacy, age, sexual orientation, and unsuitable mental health services can provide explanations as to why men and male students do not seek help for their mental health. Such findings have led to recommendations and preliminary evidence on how best to engage men with mental health support. However, there remains a paucity of research that explains how successful interventions are developed or outlines the key components used within effective interventions. Subsequently, there is a dearth of research to inform intervention content and the development process. This presents difficulties with replication, refinement, and attempts to improve our understanding of what would comprise effective interventions that could engage men and male students. Certainly, new methods and comprehensive research studies are required to develop novel interventions that meet the needs of male students who may need appropriate support. Methods: The Medical Research Council's framework for developing a complex intervention led to the development of detailed, theoretically informed, and replicable interventions for male-students. The first two stages of this framework have been followed, encompassing firstly, development and secondly, feasibility and piloting. This process included four studies: (1) a systematic review identified the specific behaviour change techniques that are embedded within previous mental health help-seeking interventions for men, (2) a qualitative focus group study explored male students' views and recommendations for the design and programme content for mental health interventions to improve male student engagement,(3) a synthesis of the systematic review, focus group results, and published literature regarding men and male student's help-seeking behaviours was employed to develop a theoretical framework about how to design effective and acceptable interventions for male students, and finally (4) a feasibility study of three pilot gender-sensitive mental health interventions for male students was conducted to assess the acceptability and uptake of the proposed interventions. Results: The first study comprising the systematic review identified through the use of BCTs seven key processes that are used with men's help-seeking interventions that encourage help-seeking. These were: the use of role-models to convey information, psycho-educational material to improve mental health knowledge, assistance with recognising and managing symptoms, active problem-solving tasks, motivating behaviour change, sign posting services and finally, content that builds on positive male traits (e.g., responsibility and strength). The second focus group study using thematic analysis revealed that key factors were: protecting male vulnerability, providing a masculine narrative of help-seeking, the intervention format, knowing when and how to seek help, and sensitive engagement strategies were important factors to consider when trying to encourage male students to seek help. The third study developed a theoretical framework using the Medical Research Council's framework for developing and evaluating complex interventions from the synthesis of the systematic review, focus groups, and published literature, which highlights the specific factors relevant to help-seeking in men and how these can be mapped onto a model of behaviour change to identify the specific techniques needed to facilitate help-seeking. Lastly, three gender-sensitive pilot interventions that incorporate the specific techniques needed to facilitate help-seeking for male students were developed and evaluated. All three gender-sensitive interventions were rated favourably and were equally acceptable, but findings indicate that the third informal drop-in intervention may be a more promising approach in order to engage hard-to-reach male students who have greater barriers to seeking help. Because this was a small feasibility study that did not follow-up further help-seeking of male students, further examination through the use of a randomised controlled trial is needed to formally test this promising approach. Conclusion: This PhD successfully addressed and provided a detailed explanation and guidance on how to develop acceptable gender-sensitive interventions that are tailored towards engaging male students with mental health difficulties. The important factors that need to be considered and embedded within mental health interventions to make them more acceptable and engaging for male students were identified and three pilot gender-sensitive interventions were developed and tested for feasibility and acceptability. These detailed intervention development processes can be more easily replicated, refined, and adapted to assist with designing more acceptable mental health interventions for male students. Further development and testing of the pilot interventions for engaging male university students are now warranted. Novel contributions to improving our understanding of men's help-seeking through the use of a systemic model of male help-seeking which incorporates male students' characteristics, attitudes as well as pre-existing mental health services for men are proposed.