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                             April 29, 2022

       Joseph M. Hogan
       President and Chief Executive Officer
       Align Technology, Inc.
       410 North Scottsdale Road, Suite 1300
       Tempe, Arizona 85281

                                                        Re: Align Technology,
Inc.
                                                            Form 10-K for the
fiscal year ended December 31, 2021
                                                            Filed February 25,
2022
                                                            Response Dated
April 21, 2022
                                                            File No. 000-32259

       Dear Mr. Hogan :

               We have reviewed your April 21, 2022 response to our comment
letter and have the
       following comment. In our comment, we may ask you to provide us with
information so we may
       better understand your disclosure.

              Please respond to this comment within ten business days by
providing the requested
       information or advise us as soon as possible when you will respond. If
you do not believe our
       comment applies to your facts and circumstances, please tell us why in
your response.

             After reviewing your response to this comment, we may have
additional
       comments. Unless we note otherwise, our references to prior comments are
to comments in our
       March 31, 2022 letter.

       Form 10-K for the Fiscal Year Ended December 31, 2021

       Consolidated Financial Statements
       Revenue Recognition, page 68

   1.                                                   We have reviewed your
response to prior comment 1 and note that you estimate usage,
                                                        which requires
significant judgment. For each of the periods presented, please tell us your
                                                        estimated usage rates.
If multiple types of estimated usage rates are used, please explain
                                                        how these were
determined. In addition, tell us the approximate impact to revenue from
                                                        any period over period
changes in estimated usage rates.
              You may contact Christie Wong at 202-551-3684 or Michael Fay at
202-551-3812 if you
       have any questions.
 Joseph M. Hogan
Align Technology, Inc.
April 29, 2022
Page 2




FirstName LastNameJoseph M. Hogan     Sincerely,
Comapany NameAlign Technology, Inc.
                                      Division of Corporation Finance
April 29, 2022 Page 2                 Office of Life Sciences
FirstName LastName