1) The article examines how CLIL (Content and Language Integrated Learning) students define authenticity from an international perspective. It discusses definitions of authenticity in EFL and CLIL, and the authenticity of purpose. 2) A mixed methods study was conducted with 103 CLIL students. The study found that students most associated authenticity with content, and saw the role of content in CLIL classrooms as very important. Students' main priorities were slightly focused on improving language skills over learning content, but both were seen as almost equally important along with study skills. 3) The article establishes the importance of authenticity in CLIL, explores how CLIL students define it, and examines the connection between learning