In recent years, there has been substantial interest in micro-credentials in post-secondary education. In November 2019, Australian skills ministers agreed to fast-track work exploring micro-credentials in the national vocational education and training (VET) system, with the aim of ensuring that the system responds more effectively to the needs of students and employers. Nevertheless, a surprising amount of other, shorter, non-qualification training occurs in the VET sector, officially known as enrolments in subjects not part of a nationally recognised program (course). This report refers to them as 'subject bundles'. This is construed in this paper as a student enrolling in a 'bundle' of subjects at a single registered training organisation (RTO), termed here 'RTO-student pairs'. This report contributes to the information already available on the largest segment of the VET sector, by analysing these subject bundles and their salient features. The author found that engagement in subject bundles was found to be typically short, with bundles of three subjects or fewer accounting for 89.5% of RTO-student pairs. Furthermore, engagement was focused on a small number of bundles (with 601 of around 50 000 bundles accounting for 90% of the RTO-student pairs) and with a relatively small number of RTOs (with 456 RTOs registering 90% of student activity). [For the technical support document, see ED612979.]