An EMS provider's post-nominal (listed after the name) credentials usually follow his or her name in this order: * Highest earned academic degree in or related to medicine (e.g. "DO") * Highest licensure or certification (e.g. "NREMT-P") * Further certifications (e.g. "CCEMT-P") Generally credentials are listed from most to least permanent. A degree, once earned, cannot be taken away. Licensure and certifications generally must be periodically renewed by examination or the completion of a prescribed number of continuing education units (CEUs).