Due to the ever-increasing expansion of English language integration into content courses within higher educational institutions (HEIs), this study seeks to gain insights into how domestic students, as well as content and language lecturers perceive integrating English for Specific Academic Purposes (ESAP) in an academic/vocational military university using Content and Language Integrated Learning (CLIL). We investigate firstly on how mostly domestic, non-native English speaking students perceive learning academic military content in an English Educational Environment (EEE), and secondly, how content and ESAP lecturers perceive collaborating within CLIL at the Swedish Defense University. Using a mixed-methods approach with data gathered from students and lecturers, the results are useful for HEIs looking to increase their English integration. Our results indicate that NNES students indeed learn content and language knowledge simultaneously using CLIL because communicative ESAP tasks enable them to process, and increase content knowledge. However, as this article will show, students prefer drastically different CLIL methods for reasons that we argue can be traced to varying L2 proficiencies. Meanwhile, lecturers had different expectations of, and perceived, interdisciplinary collaboration differently. This study concludes by suggesting that CLIL step 3 is inherently flawed due to a mismatch of implicit methods and explicit expectations of language proficiency, which consequently complicate lecturer roles and interdisciplinary collaboration.