This article summarizes the dosimetric results of an International Atomic Energy Agency coordinated research program to investigate the feasibility of adopting guidance levels for invasive coronary artery procedures. The main study collected clinical data from hospitals located in five countries. A total of 2265 coronary angiograms (CA) and 1844 percutaneous coronary interventions (PCI) were analyzed. Substudies evaluated the dosimetric performance of 14 fluoroscopes, skin dose maps obtained using film, the quality of CA procedures, and the complexity of PCI procedures. Kerma-area product (P-KA) guidance levels of 50 and 125 Gy cm(2) are suggested for CA and PCI procedures. These levels should be adjusted for the complexity of the procedures performed in a given institution. (C) 2008 American Association of Physicists in Medicine.