Exposure to adverse life events and environmental stressors (e.g. violence, poverty, sexual abuse) has been found to be high in intellectual disability populations. Notwithstanding resilience, for some people with intellectual disability, adverse life events and environmental stressors may lead to PTSD and may affect well-being in more diffuse but potentially still clinically impactful ways (e.g. challenging behaviour, obesity, substance misuse). Advances have occurred in the field of trauma in intellectual disability. More specifically, a small number of assessment measures have been developed for PTSD and a small number of studies evaluated treatment interventions such as cognitive behavioural therapy (CBT) and eye movement desensitisation and reprocessing (EMDR). Awareness has also increased regarding the potential life course effects on mental health of exposure to environmental stressors. While these developments are promising, the field warrants more research and development. This paper considers recent developments in knowledge on the psychological effects of exposure to adverse life events and environmental stressors in adults with intellectual disabilities.