<p>Intercultural competence (IC) is increasingly recognized globally as a goal of education. In Vietnam, despite emphasis on intercultural competence in national language education, research has shown the peripheral role of addressing culture in EFL classes although research on the topic of how to cultivate intercultural language teaching and learning (ICLTL) is growing. This study investigated affordances for intercultural learning through project-based learning (PBL) in an EFL program at a Vietnamese university. It followed an interpretive research paradigm and qualitative research approach. It included two related studies. Study 1 was an ethnography-informed study, which involved 14 teachers, 265 students, 6 graduates and their employers. Data were collected from classroom observations, student focus group interviews, and interviews with teachers, graduates and employers. This preliminary research revealed few opportunities for intercultural learning in this program. Specifically, it found that culture was rarely addressed, and the main instructional method for culture was fact transmission. Moreover, teachers showed limited understanding of ICLTL and students expressed the need for further culture learning. Study 2 was a participatory action research study, in which a semester-long project was introduced to foster intercultural learning. Study 2 included two workshops, one at the beginning and one in the middle of the project. In these workshops, the researcher and three teachers collaboratively learned about ICLTL, and planned PBL lessons. Drawing on a thematic analysis of classroom data and teachers’ and students’ reports, the findings showed teachers’ improved practices and understanding of ICLTL and PBL, and indications of students’ IC development throughout the project. This research contributes to the growing scholarship on ICLTL by providing evidence for the efficacy of PBL for intercultural learning. Additionally, the study highlights the impact of teacher professional development on teaching practice and extends understanding of how to incorporate PBL in a textbook-based and exam-oriented EFL context.</p>