Work is a significant factor in mental health and wellbeing outcomes. Career development processes can be helpful in finding and managing work trajectories that lead to these as well as additional wellbeing outcomes. Conversely, mental illness can impede the acquisition and retention of suitable work as well as the ability to fully engage in career development. Evidence for the interactive relationships between work, career development, mental health and mental illness is reviewed, with an emphasis on the relationships between work (both "good" and "bad") and wellbeing outcomes. Evidence for counselling/guidance interventions, organisational interventions and policy directions follow, concluding with suggestions for improving wellbeing via career development interventions.