The deadline to request a Letter of Invitation is November 1st. Complete one form per attendee, and be sure to include all required information.The official ALA letter of invitation is to be used to facilitate the processing of any visas or documents needed for you to attend the ALA conference only. Request a Congress Invitation Letter. Fill out the form below to be sent an invitation letter for visas or other purposes. Each person requesting an invitation letter must complete a separate form, and the letter will be sent in PDF form to the email address provided. Describe the Event: Offer a brief description of what the event entails. You must register for the Midwinter Meeting prior to completing the form. You are invited to attend the 85 th Scientific Sessions of the American Diabetes Association® (ADA) to be held June 20–23, 2025 in Chicago, Illinois.