To define a set of quality indicators that should be routinely measured and evaluated to confirm that the clinical outcome reaches the requested standards, Eusoma has organised a workshop during which twenty four experts from different disciplines have reviewed the international literature and selected the main process and outcome indicators available for quality assurance of breast cancer care. A review of the literature for evidence-based recommendations have been performed by the steering committee. The experts have identified the quality indicators also taking into account the usability and feasibility. For each of them it has been reported: definition, minimum and target standard, motivation for selection and level of evidence (graded according to AHRO). In overall 17 main quality indicators have been identified, respectively, 7 on diagnosis, 4 on surgery and loco-regional treatment, 2 on systemic treatment and 4 on staging, counselling, follow-up and rehabilitation. Breast Units in Europe are invited to comply with these indicators and monitor them during their periodic audit meetings.