Despite the growing interest in public and patient involvement in research, best practices in the leprosy context have yet to be explored. This mixed-method study aimed to explore the interpretation, barriers and opportunities of meaningful engagement of persons affected by leprosy in research through: (i) an exploratory phase consisting of key informant interviews with experts in public and patient involvement (n = 2) and experts-by-experience (i.e., persons affected by leprosy; n = 4), and (ii) an in-depth phase among leprosy researchers consisting of an online survey (n = 21) and key informant interviews (n = 7). Qualitative data were thematically analyzed. Basic descriptive statistics were used to summarize the survey data. Key informant interviewees unanimously agreed to the importance of engagement in research. Survey results indicated that the level of engagement differed across research stages. Identified barriers included a lack of skills for or awareness of engagement among both experts-by-experience and researchers, stigma and limited time and resources. Opportunities included capacity strengthening, creating a shared understanding, building rapport, and establishing a safe environment. In conclusion, this exploratory study emphasized the importance of engagement of experts-by-experience in leprosy research and identified ways forward that include, but are not limited to, the acknowledgement of its value and creating a shared understanding.