​​Members with a login can make changes and cancellations online via > Member Center > My Registrations. Cancellations received/processed by January 27, 2020 are fully refundable. Registrants who cancel after this date will not receive a refund. Substitutions are accepted. No shows and registrants failing to cancel prior to January 27, 2020 are responsible for paying the full registration fee. If you have difficulty cancelling online, you may contact Accounts Receivable at 703-907-6875, or fax to 703-907-5951.