This paper shares findings from the Erasmus+ project TEAM: Teacher Education Academy for Music, Future-Making, Mobility and Networking in Europe (2023-2026), one Work Package of which investigated how music student-teacher internships abroad can enrich initial teacher education. It focuses specifically on data from one implemented cycle (Spring-Summer 2025) at the [host school], where three student-teachers from [sending university] completed a two-month internship embedded in the host school’s secondary music program (ages 12-18). Building on prior scholarship highlighting intercultural development, language growth, professional and personal development and benefits for host institutions (Marx & Moss, 2011), the data is mined for instances of intercultural understanding, learning opportunities and knowledge transfer, as well as professional identity development and personal growth that mobility experiences abroad in the context of initial teacher education programmes may offer (Burton, et al., 2013; Cushner & Mahon, 2002).Data were collected via: group and individual interviews with stakeholders before and after the internship; brief yet rich, recorded student reflections (voice memos); ongoing informal mentor conversations with both student-teachers and university educators; and audiovisual artefacts (GDPR compliant images, video, teaching materials) curated during the placement and shared across sites. Ethical issues were taken under consideration throughout the research project. Two members of the research team coded the data within the MAXQDA qualitative analysis software, meeting frequently to discuss the evolving coding scheme.Prominent codes clustered around three interlocking themes: (1) intercultural understanding and linguistic development: student-teachers were called upon to swiftly adapt to unfamiliar educational and social situations in a multilingual and multicultural international school environment; (2) professional learning and competencies: role negotiation, identity development and growth in personal competencies and skills were evidenced in pre- and post-internship interviews and voice memos. Particularly interesting were perceived instances of knowledge transfer where student-teachers’ contributions and knowledge were highly valued; (3) relationship-building and support: collaboration and co-planning with peers and mentor-teachers, as well as expansive support from other local staff members, who sought to engage student-teachers as professionals within the host institution and scaffold their learning.The findings position internships abroad not merely as mobility experiences but as "bridge-building practices" that "expand the student-teacher suitcase" with culturally relevant knowledge and understandings, opportunities for professional identity formation and commitment to lifelong learning and knowledge exchange. Implications for preparing, supporting and integrating international internships into existing teacher education programmes are addressed, including the development of tools and structures of support for sending and receiving institutions.