Background: Mindfulness interventions have been shown to ameliorate stress in support staff working with people with intellectual disabilities. This review aimed to explore what impact mindfulness interventions for staff have on their care and support behaviours, and on the experiences of people with intellectual disabilities receiving support. Method: A systematic search of PsycINFO, Web of Science, ASSIA, and PubMed identified nine studies meeting the inclusion criteria. Outcomes were collated and a quality assessment tool was used to inform the critical analysis of the studies. Results: Despite identified methodological issues, positive results were consistently reported. These included reduced use of restrictive practices by staff, increased positive interactions between staff and people with intellectual disabilities, and reduced aggression displayed by people with intellectual disabilities. Conclusions: Further research in this area is required; however, this review supports the benefits of mindfulness on staff behaviour and the quality of life of people with intellectual disabilities.