Purpose <p>Employment plays a central role in social inclusion and individual well-being. Yet people living with chronic illnesses or disabilities continue to face substantial structural and workplace barriers to gaining and sustaining employment. There is a pressing need for empirical research that examines these issues. In this study, we aim to analyse the barriers to accessing and maintaining employment of people with chronic illnesses despite the existence of inclusive employment policies designed to promote their effective labour market participation.</p> Methods <p>This study investigates the employment experiences of 98 Spanish adults diagnosed with immune-mediated inflammatory diseases (IMIDs). A mixed-methods approach was used, combining quantitative survey analysis with qualitative data.</p> Results <p>The findings reveal that chronic pain, cognitive impairment, and inadequate workplace adjustments severely affect individuals’ work performance and stability. Participants described physical and psychological exhaustion, limited understanding from co-workers, and declining employability behaviours as key challenges to sustaining employment. Structural barriers, such as rigid schedules and insufficient job adaptations, further exacerbate exclusion. Overall, the results underscore how current workplace systems remain poorly equipped to accommodate the fluctuating and invisible nature of chronic illnesses, undermining true employment inclusion.</p> Conclusion <p>These findings highlight the urgent need to rethink prevailing assumptions in employment policy and organisational practice. To ensure genuine inclusion of workers with chronic illnesses or disabilities, employers and policymakers should promote the co-creation of flexible work arrangements, adapt job design and workflows, and raise awareness of invisible and fluctuating conditions. Such actions are crucial to achieving sustainable and equitable labour market participation.</p>