Many Canadians, and older adults especially, do not seek mental health services when they need them. Older adults seeking mental health services face numerous psychological, social, and structural barriers. Not only are older adults less likely to utilize mental health services, but they are also less likely to accept and engage in offered interventions. Raue and Sirey (2011) proposed a theoretical treatment engagement model for older adults with steps including identifying mental health problems, referral to specialty care, and involvement in treatment. The overarching goal of this dissertation was to explore how engaged older adults felt during the process of referral to and treatment within specialty geriatric mental health services, to identify ways this process could have been improved, and to use the suggestions made by persons with lived experience to develop a brief method of enhancing treatment engagement. In Study 1, I conducted interviews with 13 individuals 65+ with depression, anxiety, and/or stress, who had been recently referred to specialty geriatric mental health services regarding how engaged they felt during this process and how engagement could have been improved. I analyzed the data using the framework analytic method and found four main themes of background factors, modifiable individual factors, social influences on treatment engagement, and opportunities for improvement. These themes supported and expanded Raue and Sirey’s model to emphasize the role of mental health literacy, nuance concerning treatment preferences, and the dynamic and social aspects of the engagement process. Participants identified a number of opportunities to enhance engagement by improving mental health literacy. In Study 2, I employed a logic model to guide the development of a psychoeducational pamphlet for older adults referred to hospital-based geriatric mental health services. The pamphlet’s content was guided by Raue and Sirey’s treatment engagement model, interviews from Study 1, and psychoeducational resource recommendations. Finally, to ensure that patients’ needs and preferences were accurately translated into practice, Study 3 aimed to gather feedback from patients on this newly created pamphlet. In this third study, I conducted interviews (n=12) to explore patient feedback on the novel psychoeducational pamphlet and ways it may be improved. Using the framework analytic method, I coded themes of understandability, presentation, and accessibility of the pamphlet as well as themes related to overall usefulness and background factors influencing the perception of the pamphlet. Participants noted opportunities to improve the pamphlet’s content and visual presentation. Notably, participants expressed positive reactions to the pamphlet while highlighting their preference that primary care providers share this information. Overall, findings from this research provide important and additive insight on treatment engagement in older adults and ways to improve this as expressed by individuals with lived experience.