Relationship interventions, including healthy relationship education, couple therapy, and dyadic approaches to treating mental and physical health issues, hold promise for promoting relationship and individual health among sexual and gender minority (SGM) populations. Because SGM couples live within a context of societal stigma against their minority identities and relationships, they are likely to be best served by targeted, culturally sensitive relationship interventions that are affirming, free of hetero‐ and cis‐normativity, and address the unique stigma‐based challenges that they face. Therefore, a key goal for the field today is to conduct research evaluating and refining newly developed relationship interventions designed specifically for SGM couples. In this paper, we offer recommendations for effectively recruiting and retaining large, diverse samples of SGM couples for clinical trials of tailored relationship interventions, grounded in guidelines for psychological practice and conducting research with SGM populations. Throughout, we offer examples and lessons learned from our experiences conducting clinical trials of tailored SGM relationship education programs. We encourage the use of recruitment and retention strategies that involve members of the target SGM community from the outset, are informed by knowledge about SGM individuals and relationships, use currently preferred language for individual identities and relationships, attend to issues of confidentiality regarding sexual/gender identity or relationship involvement, and adhere to the norms of the particular community and recruitment venue.