Background Researchers identified “preparing patients to be active in innovations” as one of the top five most effective implementation strategies; this included educating patients to be engaged in their care. If engaging patients in their own care enhances adoption of innovations, engaging patients and service users across any setting (e.g., healthcare, education, carceral) in implementation activities may also enhance adoption. To provide guidance on this topic, we developed Consumer Voice: a free, online platform for community engagement in implementation efforts. In July 2023, we disseminated the tools and received feedback that “consumer” had a negative connotation for some. This feedback mimicked discontent with terminology for the “service user” in the broader implementation field. Our study goal was to identify inclusive, acceptable terminology for the “service user” in implementation practice or research.Methods We collected quantitative data then qualitative data from service users, implementers, and implementation researchers in two phases: 1) Brainstorming and prioritizing terminology for service users through Nominal Group Technique, then 2) Contextualizing implications of different terms through focus groups. Between phases, we used quantitative counts to inform sampling and inductive qualitative analysis.Results Participants represented a range of demographic groups; over 40% identified primarily as individuals receiving health services, 30% as implementers, and 26% as implementation researchers. There was consensus to rename our engagement tools “Engaging All Voices.” Our data indicated there was no universally acceptable term for “service user.” Even within similar communities, some terms were controversial e.g., “patient,” “peer.” Two terms felt off-limits to most: “stakeholder” and “user.” Participants thought any engagement language should convey a sense of action and partnership to move beyond performative, superficial “engagement.”Conclusions We sampled people from multiple service settings and thus, findings may generalize in healthcare, education, carceral, and other systems. Our experience redesigning Engaging All Voices revealed that how recipients of innovations are referred to can shape receptiveness to engagement approaches. There is no single “right” term to refer to service users across settings. Engaging All Voices now guides learners in an early exercise to determine terminology preferred by service users throughout an implementation effort.