Irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction that affects 3.5% of Australians and is characterised by abdominal pain and altered bowel motions(1). People with IBS have described low treatment satisfaction from healthcare providers and services, citing a lack of person-centred care(2). This is concerning given that the dietary management of IBS using the low fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) diet (LFD) is the most efficacious dietary treatment for global symptom improvement(3). This study aimed to explore people with IBS’s experiences of a dietetic-mediated LFD and identify strategies for optimising LFD implementation. A qualitative descriptive study design involved semi-structured interviews with adults with IBS who participated in a dietetic-led research study on predictors of response to the LFD. Participants who commenced at least one of the three LFD phases between October 2020 and April 2022 were invited to participate. An inductive, iterative process was used to code participant transcripts and confirm the final themes. Themes were mapped against the Theoretical Domains Framework (TDF) and Behaviour Change Wheel (BCW) to inform interventions to optimise the delivery of the LFD. Seventeen adults (32%, 17/53 response rate) aged 39 ± 15 years and 88% female-identifying consented to interviews. All phases of the LFD were completed by n = 9, with n = 4 completing Phases 1 and 2, n = 1 completing Phase 1 only and n = 3 commencing but not completing the first phase. Two main themes emerged. Firstly, patients wanted more dietetic appointments and support to implement the LFD. Participants wanted more frequent dietetic contact (approximately halfway through Phase 1, early to mid-Phase 2 and three to six months after commencing Phase 3) and appointments that were tailored to their individual needs and circumstances (face-to-face, phone and/or email) in each phase to troubleshoot diet implementation and manage symptoms. Further, more detailed education materials were requested, including recipes, acceptable foods, including commercial foods, and meal plans. Secondly, participants wanted a person-centred, multidisciplinary care approach with health professionals working together to be considered, given the complexity of IBS, especially with incomplete symptom resolution with the LFD. Participants recognised that stress, general anxiety and lifestyle factors contributed to symptoms and further support beyond the LFD was required. When mapped to the TDF and BCW, it was evident that environmental context and resources, knowledge, skills, beliefs and capabilities of the TDF and restructuring of the environment, education, training and self-monitoring domains of the BCW overlapped. The findings emphasise the need for a more person-centred care model using varied modes of delivery designed to suit individual needs and behaviour change requirements. Implementing multidisciplinary care, alongside behaviour change techniques, may assist treatment completion and IBS management.