Background In 2007, ESAC (http://www.esac.ua.ac.be) published a set of 12 valid drug-specific quality indicators for outpatient antibiotic use in Europe. In this study, the authors aimed to develop evidence-based disease-specific quality indicators for outpatient antibiotic prescribing in Europe. Methods Two meetings were convened to produce a list of disease-specific quality indicators for outpatient antibiotic prescribing which conform to internationally agreed recommendations, building on a similar development of drug-specific quality indicators, and in collaboration with CHAMP and HAPPY AUDIT. 62 experts were asked to complete two scoring rounds of the proposed indicators on seven dimensions: their relevance to (1) reducing antimicrobial resistance, (2) patient health benefit, (3) cost-effectiveness, (4) policy makers, (5) individual prescribers, (6) their evidence base and (7) their range of acceptable use, using a scale ranging from 1 (=completely disagree) to 9 (=completely agree). Scores were judged according to the UCLA-RAND appropriateness method. Results For the six main indications for antibiotic prescribing (acute otitis media, acute upper-respiratory infection, acute/chronic sinusitis, acute tonsillitis, acute bronchitis/bronchiolitis, cystitis/other urinary infection) and for pneumonia, three quality indicators were proposed, the percentage prescribed (a) antibiotics; (b) recommended antibiotics; (c) quinolones. This set was scored by 40 experts from 25 countries. After one scoring round, all indicators were already rated as relevant on all dimensions, except one. Conclusion All proposed disease-specific quality indicators for outpatient antibiotic prescribing have face validity and are potentially applicable. They could be used to better describe antibiotic use and assess the quality of antibiotic prescribing patterns in ambulatory care.