Background Acute gastroenteritis is a highly contagious disease demanding effective public health and clinical care systems for prevention and early intervention to avoid outbreaks and symptom deterioration. The Netherlands and Australia are both top-performing, high-income countries where general practitioners (GPs) act as healthcare gatekeepers. However, there is a lower annual incidence and per-case costs for childhood gastroenteritis in Australia. Understanding the systems and policies in different countries can lead to improvements in processes and care. Therefore, we aimed to compare public health systems and clinical care for children with acute gastroenteritis in both countries. Methods A cross-country expert study was conducted for the Netherlands and Australia. Using the Health System Performance Assessment framework and discussions within the research group, two questionnaires (public health and clinical care) were developed. Questionnaires were delivered to local experts in the Netherlands and the state of Victoria, Australia. Data synthesis employed a narrative approach with constant comparison. Results In Australia, rotavirus vaccination is implemented in a national program with immunisation requirements and legislation for prevention, which is not the case in the Netherlands. Access to care differs, as Dutch children must visit their regular GP before the hospital, while in Australia, children have multiple options and can go directly to hospital. Funding varies, with the Netherlands providing fully funded healthcare for children, whilst in Australia it depends on which GP (co-payment required or not) and hospital (public or private) they visit. Additionally, the guideline-recommended dosage of the antiemetic ondansetron is lower in the Netherlands. Conclusions Healthcare approaches for managing childhood gastroenteritis differ between the Netherlands and Australia. The lower annual incidence and per-case costs for childhood gastroenteritis in Australia cannot solely be explained by the ...