The number of hospitals with antibiotic stewardship (ABS) activities to improve and ensure rational use of antibiotics is rising. Therapy optimisation is suggested by the interdisciplinary ABS-team during proactive audit of antiinfective use. These recommendations, referred to as ABS-interventions, enhance quality of prescribing regarding choice of substance, dose, dosing interval, route of administration and duration of treatment. We developed an evidence-based tool for documentation of these quality-assuring activities and subsequently demonstrating the value of antibiotic stewardship programmes.