Magnetic resonance tomography is an effective imaging modality for assessing anatomy and the state of tissues of the region in question without using ionizing radiation. However, because of the application of a strong static magnetic field, there can arise issues related to the examination of patients with different implants and/or medical devices. In this article we discuss the different aspects of imaging safety in patients with implants, different medical devices, as well as potentially magnetic foreign bodies and pigments. The most important interactions are heating and implant/device movement which can potentially harm the patient and the implant/ device. In order to ensure patient safety, appropriate information about the implant/ device is needed beforehand.