Second language learning is a complex and dynamic process, which includes not only learners’ cognitive development, but also their socialization into the local community. From this perspective, context plays a crucial role in socialization and language learning.  Similarly, learning environments of language programs may have a powerful influence on the success in L2 acquisition. Based on the experiences of two ESL students enrolled in an intensive English program that enforced an English-only policy, this article discusses the social aspect of institutional policies and the effect they may have on learners’ language socialization. The author argues that program administrators need to carefully consider the role of contextual factors when analyzing learners’ social and linguistic behavior, so they can better understand how to maximize learners’ enculturation and language development. Keywords: L2 socialization, L2 acquisition, ESL, case study,