Background: The Australian Childhood Immunisation Register (ACIR), established in 1996, captures details of vaccinations given to children aged <7 years, expanded in 2016 to the whole-of-life Australian Immunisation Register (AIR). Objective: Overview of ACIR/AIR, how health information captured is managed and how AIR data facilitate insights into vaccination reporting trends. Method: The authors, with 58 years of collective experience in analysing and interpreting ACIR/AIR data, reviewed formal and grey literature relevant to ACIR/AIR and their operation and use. We analysed AIR data to document how data transmission to AIR and vaccination provider settings has evolved. Results: We describe policy and program changes instrumental to the ACIR-AIR expansion, AIR data fields, methodology for measuring population-level vaccination coverage, and ways data are used for: monitoring and evaluation of immunisation programs; public health surveillance; linked data analyses; vaccine effectiveness studies and other research. We show evidence of changing vaccination landscape including increasing trends in electronic data transmission (e.g. proportion of vaccinations given to children aged <10 years and notified to ACIR/AIR using practice management software increased from 56% in 2014 to 89% in 2023) and increase in vaccinations given in pharmacies (e.g. proportion of influenza vaccinations given to adults aged 20–64 years in pharmacies increased from 0.9% in 2017 to 26.9% in 2023). Conclusion: The AIR has been instrumental in monitoring and evaluating the reach and impact of Australia’s publicly funded immunisation programs across the life course. Implications for health information management practice: Health information managers working with vaccination data contribute to the AIR through data management and upload to the AIR.