This study presents a comprehensive analysis of ten years of data from the Irish National Outpatient Parenteral Antimicrobial Therapy (OPAT) registry. Initiated in 2013, the Irish OPAT programme is a centralised model which collates data from all referrals to the National OPAT programme. Data from 39 institutions revealed 17,558 OPAT episodes, involving 12,725 unique patients, with a steady increase in usage until a decline in 2021–2022 attributed to the COVID-19 pandemic. The majority of care was delivered through health professional administered OPAT (H-OPAT), with a smaller but increasing proportion via self-administered OPAT (S-OPAT). Key findings include a median patient age of 59, a median treatment duration of 19.2 days, and significant variation noted in treatment durations and condition usage across hospitals. Ceftriaxone emerged as the most prescribed antimicrobial. The registry highlighted the programme's impact on bed day savings, with a total of 292,825 days saved over the decade. Variances in treatment practices were observed, pointing to the need for ongoing evaluation of antimicrobial stewardship and treatment protocols. The study underscores the importance of national registries in monitoring and improving OPAT services and calls for integration of microbiological data to enhance stewardship. Future directions include adapting to emerging evidence favouring oral over parenteral therapy for certain conditions, and how these complex patients can be managed and integrated within an OPAT structure.