IROCA (Improving Radiation Oncology using Clinical Audits) is a project in which six EU institutions (Radiotherapy departments from Cancers Centres) have been participating since 2008. Ever since, three rounds of IROCA have been completed and a number of papers published on the topic. We audited and compared practices for radiotherapy of rectal and prostate cancers (specific inclusion criteria apply). Improving quality of radiotherapy requires constant evaluation of key elements of care. In order to foster the quality and efficacy of radiotherapy, we decided to establish a joint project aimed at interinstitutional comparison of chosen quality indicators in radiotherapy procedures.