Background: Working and interacting with people from diverse backgrounds have become common in Engineering. Research has indicated that engineering graduates face challenges while working with a diverse workforce. Therefore, it is vital for higher education institutions to help engineering students develop intercultural competence skills by engaging them in intercultural learning activities. This study explores the impact of a semester-long study abroad program and its new curriculum on the intercultural learning gains of undergraduate engineering students. The study used a mixed methods design to assess the intercultural learning gains of the students enrolled in a study abroad program. Results: The results of the study indicated that overall, as a group, students demonstrated significant gains in their Intercultural Development Inventory (IDI) scores from the pre- to post-test. Moreover, hierarchical clustering was conducted to group students into three clusters based on their IDI scores. The results of the clustering helped us to understand the differential growth of students from their pre- to post-test. Based on clustering students were grouped into high, moderate and low intercultural learning clusters. Further inductive thematic analysis was conducted to understand the depth of intercultural awareness of the students in general and discipline specific for each cluster. The results of the thematic analysis revealed that students in cluster 1 showed a deeper understanding of cultural differences, mindfulness, and openness while interacting with people from other cultures, whereas the students in clusters 2 and 3 showed moderate to superficial level of intercultural awareness. Conclusions: The implication of the study extends to both practice and theory. From the practice perspective, the study discusses the need for creating intentionally structured study abroad programs that encourage students to reflect on their intercultural experiences and internalize takeaways. From the theory perspective, the study contributes to the Intercultural Development Continuum model, as it emphasizes the importance of meaningful gains in intercultural competence. The study also suggests strategies to improve the intercultural learning experiences of students that could help them move towards more intercultural mindsets.