Mathematics Education Researchers' work in interdisciplinary research groups can be enriching and challenging in terms of communication, work processes, institutional support, and the translation of findings into viable results for existing disciplines. We contend that there is a need to explore practices (i.e., ways of being, operating, and interacting with others) in these groups. We searched Scopus and ERIC databases to find published works of interdisciplinary groups involving at least one Mathematics Education Researcher, which led us to five articles in peer-reviewed mathematics education journals. Thematic analysis of these articles helped us identify three practices: (1) working toward research interests, (2) cultivating trust and open-mindedness, and (3) understanding institutional support. We argue that consideration of these practices can facilitate Mathematics Education Researchers' interdisciplinary collaborations. Further research documenting Mathematics Education Researchers' interactions within interdisciplinary research groups is needed.