Endovascular application of suitable radiation sources is one of the treatment modalities to prevent restenosis after percutaneous coronary and peripheral interventions. The procedure is highly interdisciplinary in nature, involving at least one interventionist (e.g. cardiologist, angiologist, radiologist or surgeon), a radiation oncologist and a medical physicist. This publication meets the need to disseminate information on a number of incidents that have resulted in undue radiation exposure of personnel and patients, with a view to preventing similar occurrences in the future. The publication has been written in a straightforward manner and is primarily directed at physicians involved with the use of radioactive sources for endovascular interventions. It will also be useful for medical physicists, radiation oncologists and hospital administrators in introducing to them the types of event that can occur in such applications.