Sessions of the International Congress on Medieval Studies hosted by Western Michigan University, which are 90 minutes long, are constituted as follows:
- Sponsored sessions are organized by learned societies, associations, institutions and research projects. The organizers set predetermined topics, usually reflecting the considered aims and interests of the organizing group.
- Special sessions are organized by individual scholars and ad hoc groups. The organizers set predetermined topics, which are often narrowly focused.
- General sessions are organized by the congress committee at the Medieval Institute. Topics include any area of medieval studies, with individual session topics determined by the topics of paper proposals submitted and accepted.