Organizations increasingly operate in diverse languages to serve external stakeholders, yet often adopt monolingual practices for internal work processes. As language is both a skill and a source of identity, low-status language speakers may experience identity-based exclusion in such organizations, regardless of their common corporate language skills. We thus explore how linguistic inclusiveness can emerge among tensions between the demands for multilingual services and the need for a lingua franca in organizations. Grounded in a qualitative study of a Russophone bank in Kazakhstan, we theorize how actors with different linguistic and sociocultural backgrounds engage in sociolinguistic work—that is, everyday actions that shape practices surrounding the use of a particular tongue within an organization—in the context of changing linguistic dynamics in society. Through sociolinguistic work, members of marginalized, in-between, and dominant groups respond to societal changes and influence others' perceptions of languages and behaviors, ultimately reshaping internal linguistic dynamics over time. By conceptualizing language as an important dimension of diversity, theorizing the emergence of linguistic inclusiveness through sociolinguistic work, and highlighting the critical role of an in-between group in this process, we advance research at the intersection of languages and inclusiveness in organizations.