Purpose: The author is interested in how international (migrant) pre-service teachers use their educational background knowledge and worldviews to make sense of the educational system, the pedagogy and of power relations between staff members in the hosting country. The author seeks to unveil their understanding of successful intellectual integration and their strategies to navigate social, conceptual and pedagogical obstacles. Design/methodology/approach: The author draws on the concept of "intercultural competence" to analyse how international STEM pre-service teachers respond to the challenges and opportunities of integration in the English system. A total of 18 participants were interviewed in focus groups in London to find out about their perceptions of the course and attitudes during their training journey. Five hours of audio recording were transcribed and a thematic analysis was carried out. Findings: International STEM pre-service teachers experience challenges to intellectual integration, including understanding the new school culture, school structure, teaching methodologies and the use of specialist terminologies. However, they show little concern about networking and relations of power. Practical implications: Mentors and tutors should not assume school systems are the same everywhere. Support from university tutors and school mentors must take into consideration that international students will very likely hold ethnocentric views. Mentors, tutors and pre-service teachers would benefit very much from bespoke support to help international students to integrate in a new educational system. Originality/value: Very little has been reported on the experience of international STEM pre-service teachers in England, particularly those with no previous teaching experience. The objective of this study is to address this gap and contribute to the internationalisation of teacher training curricula.