Ambulatory emergency care units are present in many hospitals and accommodate patients who need urgent medical assessment or procedures but do not require inpatient admission to achieve this. This article reports on a project undertaken in the ambulatory care unit at the Royal United Hospital Bath, which introduced a nurse-led paracentesis service with the intention of reducing waiting times and improving the service for patients. To evaluate the effect of the project, patient satisfaction levels and waiting times were measured before and after the introduction of nurse-led paracentesis. The results confirmed a significant reduction in waiting times after the nurse-led intervention was introduced and high levels of satisfaction. The results provide evidence that nurses are acquiring the knowledge and skills required to undertake interventional procedures that improve the patient’s experience while contributing to pioneering developments in ambulatory emergency care services.