Background: Traineeships have been proven to be beneficial vocational pathways for people with intellectual disability however to date the on-the-job training provision associated with traineeships has not been well documented. Method: This study describes components of on-the-job training provided to eight people, most with intellectual disability undergoing traineeships for 12 months in four aged care services. Sheri et al.'s (2019) framework for mentors during training was used to examine the findings. Results: Challenges in the traineeships were common to most new staff, such as developing confidence, recognising the urgency of some tasks, and time to learn how to support aged-care residents. The findings highlighted on-the-job training that was individualised, incorporating a variety of approaches was most beneficial to the trainees. Conclusions: Traineeships for people with intellectual disability require support from both the trainee and mentors. This support is essential to develop skills and ensure positive workplace attitudes.