No longer than three years. The ACCME policy on enduring materials requires both an original release date and an expiration date. In addition, the ACCME policy requires that you review each enduring material at least once every three years or more frequently if indicated by new scientific developments. So, while you can review and re-release an enduring material every three years (or more frequently), the enduring material cannot be offered as an accredited activity for more than three years without some review on the part of the provider to ensure that the content is still up-to-date and accurate. That review date must be included on the enduring material, along with the original release date and an expiration date. For more information, see the ACCME's policies regarding enduring materials.