The development of critical thinking skills forms an important part of many higher education courses and has become increasingly visible in syllabi and assessment criteria. Yet, in spite of this, students often struggle to understand what it is and to demonstrate it in their work. This paper aims to explore how students understand the term critical thinking and to identify some of the key factors which influence this. An in-depth case study was conducted with four first-year undergraduate students in the education faculty of a university in England. Data were collected through thematic interviews and stimulated recall interviews. Key findings highlight that students believe strongly in the importance of developing critical thinking skills, yet while they can speak relatively easily about more abstract definitions of the term, they often find it difficult to do and to identify in their own work. Findings suggest that their conceptualizations are influenced by their prior educational experiences and vary according to discipline. Implications for pedagogy include the need for explicit guidance on critical thinking, the provision of substantial opportunities for practice, and the need to engage in dialogue across disciplines to highlight opportunities for promoting connection-making and transfer between different contexts.