Online learning environments are changing the landscape of education, with evidence supporting their efficacy. However, research that focuses entirely on online distance English-language programs is sparse, especially in regards to oral proficiency. The purpose of this study is to investigate the efficacy of an online distance-learning program in helping students develop oral English-language proficiency as they prepare to attend a university in the United States. The curriculum for the distance-learning program was built upon Moore's transactional distance theory, with an emphasis on interpersonal dialogue as a key tool in promoting oral proficiency. Students participated in synchronous and asynchronous interaction with fellow students, tutors, and their instructors. The American Council on the Teaching of Foreign Languages (ACTFL) computer-assisted Oral Proficiency Interview (OPIc) provided the pretest and posttest measures for this study. To supplement this data, course surveys provided information concerning student opinions of course activities. OPIc results showed that students made significant gains in their oral proficiency from pretest to posttest. In surveys, students rated interaction with other tutors and teachers as instrumental in assisting them with their language learning, but rated interaction with their peers as less helpful.