Background: Restraint is sometimes used on people with intellectual disabilities who display challenging behaviours, and may be justifiable as a last resort to prevent harm. A substantial proportion of such people are cared for within the family home. The aim of this paper is to explore parents' experiences of using restraint with their son/daughter with intellectual disabilities. Materials and Methods: Seven participants took part in the study. Interpretative Phenomenological Analysis (IPA) was used to analyse the interviews, due to its dual perspective of understanding of participants' experiences and acknowledging the interpretative process of the research. Results: Restraint was described as a "very fine line", drawn in an attempt to strike a balance between right and wrong, safety and danger, humanity and dehumanising, and helping and harming. Interactions regarding restraint with professionals also presented a fine line between being heard and being ignored, being supported and being isolated, and being informed and being kept in the dark. Conclusions: Decisions about restraint present many complex dilemmas. It is recommended that professionals can support parents pro-actively by providing advice on challenging behaviour and sufficient support in the caring role. Where restraint is necessary support can be provided by recognising the complexity of such decisions, working in partnership with parents, promoting a culture of openness and honesty about restraint use in services, and providing training and advice about restraint.