This dissertation study investigates the complexities of the relationship between literacy and international development in Indonesia. I focus on the Literacy Boost program from the international non-governmental organization Save the Children, and I explore how the program was differentially implemented and received in two sites: mega-metropolitan Jakarta, and Belu Regency, a largely rural region in Eastern Indonesia. Drawing on thirteen months of ethnographic research conducted between 2016-2017, I identify both intended and unintended outcomes of the Literacy Boost program. I highlight the tension between the core Literacy Boost program components, standards, and practices, and the program's heterogenous manifestations in the two sites. I find that in each site, Literacy Boost had to confront systemic challenges at schools before and while implementing literacy programming. Whereas in Jakarta, Literacy Boost focused on issues related to school-based management, in Belu, it focused on banning corporal punishment in classrooms. Thus, Literacy Boost produced different short- and long-term impacts across the two sites, none entirely predictable nor coincidental. My analysis discerns how these distinct trajectories of development unfolded and were experienced by an array of Literacy Boost stakeholders. Furthermore, I explore how Literacy Boost programming was shaped by the exigencies of international development practice, including evaluation requirements and time constraints. These shared constraints notwithstanding, I show how in each site Literacy Boost was modulated by the distinct linguistic context, infrastructure and accessibility, and local notions of progress and development. In demonstrating how a literacy intervention has been taken up in situated contexts of teaching and learning, this dissertation contributes to the understanding of how international development processes succeed and falter across geographic, linguistic, and cultural contexts.