Symposia are 90 minutes in length and include a chairperson or moderator and up to five presenters who offer their perspectives on a single issue. Typically, a symposium includes four presenters and one discussant or five presenters and no discussant. It is desirable that a symposium include participants from a variety of countries or institutions. A symposium should provide an opportunity for audience discussion and involvement. The chairperson is responsible for submitting abstracts for the overall symposium as well as for the included presentations.