MRI is a powerful diagnostic tool; however, it is relatively contraindicated for patients with cardiovascular implantable electronic devices (CIEDs) such as pacemakers and implantable defibrillators. Several interactions with CIEDs have the potential to cause harm, and fatalities have been reported. Limited experience of MRI in patients with CIEDs under close supervision and utilizing specific scanning protocols has emerged from a small number of centers. Even then, adverse effects on the CIED have been reported. The recent development of MRI-conditional pacemaker systems and the demonstration of safe magnetic resonance scanning in a large clinical trial (EnRhythm MRI™ SureScan™ Pacing System Study) is a significant advance in the care of patients with CIEDs, opening up this important imaging modality to those previously denied it. Further development of MRI-conditional CIEDs, including implantable cardioverter-defibrillators, is expected but presents many technological challenges.