The overarching purpose of Extension is to facilitate the application of science to the broader public. To achieve this goal, the information we disseminate must be accurate, relevant, socially just, and beneficial, which requires rigorous evaluation to ensure (Braverman & Arnold, 2008; Monk et al., 2021). In this chapter, I demonstrate the complementarity of Extension and the process of research and evaluation by outlining the relevance of Extension as a (a) research-informed, (b) evidence-based, (c) culturally relevant, (d) interdisciplinary, and (e) public-scholarship enterprise. To illustrate each of these qualities of Extension, I will describe the ongoing development of a relationship-science dissemination program, Relevate. In its over 100 years of existence, Extension has been at the forefront of community-engaged, translational and transformative scholarship. The landscape of Extension has changed over time. However, shifts and challenges in engagement work can also represent new opportunities to be responsive and innovative. Extension is well positioned to continue carrying bringing research to the community and conducting impactful, innovative, and engaged scholarship.

This chapter introduces the book and is organized around the six most basic yet critical questions that cut across all research: Who, What, When, Where, Why, and How. In the first section (“who”), we discuss the types of people who perform relationship maintenance as well as differences among people. The “what” section identifies the central definitional issues that continue to plague the field. The third section (“when”) highlights the conditions under which people perform maintenance as well as the relationship challenges that prompt it. The “where” section identifies the small body of literature on geographic differences in relationship maintenance. The “why” section covers the principal theories that explain engagement in relationship maintenance activities. The final section comments on “how” maintenance activities sustain or enhance relationships. That is, it outlines the correlates, mediators, and moderators that explain the mechanisms by which maintenance operates. We conclude our chapter with a brief overview of the organization of the book.