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                                                                    EXHIBIT 18.1

                                                      Arthur Andersen LLP
                                                      45 South Seventh Street
                                                      Minneapolis, MN 55402-2800
                                                      Tel 612 332 1111
     February 1, 2000

     Hutchinson Technology Incorporated

     Re: Form 10-Q Report for the quarter ended December 26, 1999

     Dear Ladies and Gentlemen:

     This letter is written to meet the requirements of Regulation S-K calling
     for a letter from a registrant's independent accountants whenever there has
     been a change in accounting principle or practice.

     We have been informed that, as of September 27, 1999, the Company changed
     from the last-in, first-out (LIFO) method of accounting for inventories to
     the first-in, first-out (FIFO) method. According to the management of the
     Company, this change was made due to permanent and significant declines in
     inventory conversion costs due to technological advances that are
     significantly affecting inventory costs through productivity gains.
     Additionally, substantially all of the Company's peer group utilizes the
     FIFO method.

     A complete coordinated set of financial and reporting standards for
     determining the preferability of accounting principles among acceptable
     alternative principles has not been established by the accounting
     profession. Thus, we cannot make an objective determination of whether the
     change in accounting described in the preceding paragraph is to a
     preferable method. However, we have reviewed the pertinent factors,
     including those related to financial reporting, in this particular case on
     a subjective basis, and our opinion stated below is based on our
     determination made in this manner.

     We are of the opinion that the Company's change in method of accounting is
     to an acceptable alternative method of accounting, which, based upon the
     reasons stated for the change and our discussions with you, is also
     preferable under the circumstances in this particular case. In arriving at
     this opinion, we have relied on the business judgment and business planning
     of your management.

     We have not audited the application of this change to the financial
     statements of any period subsequent to September 26, 1999. Further, we have
     not audited and do not express any opinion with respect to your financial
     statements for the period ended December 26, 1999.

     Very truly yours,
     /s/ Arthur Andersen LLP