This paper reports findings from a 12-month Australian study exploring beliefs and experiences of disclosure and course success in post-compulsory education for 20 students with mental illness. Enrolled students with disclosed or non-disclosed mental illness, teaching and support staff, and institutional practices across four sites providing vocational education and training were the three cases selected for this collective case study. Students participated in two semi-structured interviews over the course of one academic year. Disclosure was not preferred by students, most fearing that it would negatively impact upon their capacity to obtain employment in the occupation for which they were training. Further research exploring the processes, timing and outcomes of disclosure, in a wide range of post-secondary settings and with larger numbers of students, would allow for a deeper exploration of issues raised by this small study.