(1) Background: Although HIV has not diminished in importance in Canada, the field of HIV research remains small, and the graduate students who decide to pursue careers within it feel isolated and uncertain about their professional skills and opportunities. Universities Without Walls (UWW) was created in 2009 to help redress these shortcomings. This paper presents a case study of UWW, a non-credit training program for emerging HIV researchers in Canada. In particular, we focus on the possibilities of experiential learning via online and blended delivery. UWW uses both online and in-person teaching modalities to teach engaged scholarship, interdisciplinarity, community-based research (CBR), intervention research, and ethics. (2) Methods: Using a case study, we elucidated the research question: "What are the factors that make Universities Without Walls a viable training environment in the contemporary HIV/AIDS field?" Focus groups were conducted with 13 UWW key stakeholders in 2012 during a program mid-point evaluation; in 2014, telephone or in-person interviews with the three directors were conducted by a UWW fellow (the 4th author of this paper), and in 2019 the authors analyzed the information and anecdotal evidence, which had been incorporated as thick description. In addition, fellows' self-assessments via portfolio and results from formal learning assessments were included. We also thematically analyzed 65 student self-reports (2009-2015). (3) Results and Discussion: Each UWW cohort lasted 9 months to one year and was comprised of: a) sustained mentorship from the co-directors (e.g., phone conversations, assistance with grant writing, letters of reference, etc.); b) fortnightly online webinars that aim to develop fellows' knowledge of community-based research (CBR), research ethics, intervention research, and interdisciplinary research; c) community service learning in the form of a "field mentoring placement"; d) face-to-face engagement with fellows and mentors, most notably at the week-long culminating learning institute; e) a stipend for fellows to carry out their training activities. The UWW pedagogical framework features experiential learning, critical pedagogy, and heutagogy made manifest in the field mentoring placements (community service learning), mentorship mediated by technologies, and in-person learning institutes. Our analysis showed that experiential learning was imparted by UWW's a) transparency about its "implicit curriculum", the attitudes, values, character, and professional identity imparted in the program as well as the overarching programmatic elements, such as commitment to diversity, the inclusion of those with lived experience, the flexible admissions policies and procedures, interdisciplinary faculty, flexible team, administrative structure, and valuing of technology in conducting research, learning, and teaching; b) curriculum co-designing and co-teaching, and c) sustaining a community of practice. The main results reported in our case study included significant "soft outcomes" for UWW fellows, such as developing a "social presence" as a precursor to lasting professional connections; learning to experience community-based research, intersectionality, and interdisciplinarity by interacting online with persons living with HIV, leaders in the field, and a variety of stakeholders (including nonprofit staff and policymakers). (4) Limitations: While fellows' self-evaluation data were collected by an independent assessor and anonymized to the extent this was possible, the co-authors inevitably bring their preconceptions and positive biases to UWW's assessment. As UWW was developed to function outside of traditional academic structures, it is unlikely that the UWW program could be transferred to a post-secondary environment in its entirety. UWW was also built for the socio-political environment of HIV health research. (5) Conclusions: The experiences of those involved with UWW demonstrate that explicit curricular components-such as interdisciplinarity, community-based research, intervention research, and applied ethics-can be learned through a blended delivery when combined with opportunities to apply the knowledge in ways, such as a field mentoring placement and a learning institute. Related to this outcome, our case study describes that implicit curricular components in the formation of a professional-the sense of self in the field as a researcher, student, and community member-can also be delivered through a blended model. However, the tools and activities need to be tailored to each student for their context, while pushing their disciplinarian and professional boundaries.