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                                                                 Exhibit 10.27.1


                                  AMENDMENT TO
                              EMPLOYMENT AGREEMENT

        This Amendment is made and dated December 17, 1999 by and between
Novellus Systems, Inc., a California corporation (the "Company"), and Richard
Hill ("Executive") (collectively, "the parties") with respect to that certain
Employment Agreement between the parties dated October 1, 1998 (the
"Agreement").

                                    RECITALS

        1.     Executive has been employed by the Company and is currently
serving as the Chairman and Chief Executive Officer pursuant to the terms and
conditions of the Agreement dated October 1, 1998.

        2.     The parties now desire to amend certain terms of that Agreement
upon the following terms and conditions.

                                    AGREEMENT

        ACCORDINGLY, the parties agree as follows:

        1.     ADDITION OF PARAGRAPH 1(b). Following Paragraph 1(a) of the
Agreement, the parties hereby add the following Paragraph 1(b), entitled
"Renewal":

               b.     RENEWAL. The term and provisions of this Agreement shall
                      automatically extend for additional one-year periods if
                      Executive remains employed on and after December 31 of
                      each year during the Basic Term of this Agreement, unless
                      either party notifies the other in writing to the contrary
                      at least three (3) months prior to the applicable December
                      31 date that it, or he, does not want the term to so
                      extend.

               2.     AMENDMENT OF PARAGRAPH 3(a). Paragraph 3(a) of the
Agreement (regarding Executive's salary) is hereby amended in its entirety to
read as follows:

               a.     The Company shall pay Executive at an initial base annual
                      salary of $615,000.00, payable bi-weekly. Executive's
                      salary will be reviewed from time to time in accordance
                      with Company's established procedures for adjusting
                      salaries for similarly situated employees. Executive shall
                      also be eligible to participate in the Company's executive
                      bonus plan, as already established by the Company, and as
                      may be amended from time to time in the Company's sole
                      discretion.



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        3.     AMENDMENT OF PARAGRAPH 3(c). Paragraph 3(c) of the Agreement
(regarding the two relocation loans made by the Company to Executive in June and
July 1997) is hereby amended in its entirety to read as follows:

               c.     The two relocation loans made by the Company to Executive
                      in June and July 1997, as evidenced by the two promissory
                      notes, shall be repaid in full by Executive. However, the
                      Company shall forgive any interest that accrued on the
                      relocation loans to date and shall, through March 31,
                      2000, forgive any additional interest on the two
                      relocation loans.

        4.     AMENDMENT OF PARAGRAPH 4(c)(iii). Paragraph 4(c)(iii) (regarding
the Company obligation to pay for Executive's share of health insurance premiums
in the event of a Termination of Executive's Period of Employment by the Company
Not for Cause) is hereby amended in its entirety to read as follows:

               (iii)  Payment of Executive's share of health insurance premiums
                      for Executive and his qualified dependents, in accordance
                      with the Company's existing officer retirement health
                      benefit program, as evidenced by the July 1993 Board of
                      Directors' Resolution Regarding Officers' Retirement,
                      Medical and Dental Coverage without regard to age or
                      length of service limitations therein.

        5.     REMOVAL OF PARAGRAPH 4(c)(v). The parties hereby rescind
Paragraph 4(c)(v) (regarding Executive's obligation to repay the Company for the
relocation loans in the event of a Termination of Executive's Period of
Employment by the Company Not For Cause).

        6.     ADDITION OF PARAGRAPH 4(c)(v). The parties hereby add the
following Paragraph 4(c)(v):

               (v)    Executive's restricted stock shall immediately vest on the
                      date his termination becomes effective and, as a
                      consequence, the Company's right to repurchase such
                      restricted stock shall immediately lapse on that date.

        7.     AMENDMENT OF PARAGRAPH 4(e). Paragraph 4(e), entitled "By
Executive Not for Cause," is hereby amended in its entirety to read as follows:

               c.     BY EXECUTIVE NOT FOR CAUSE. At any time, Executive may
                      terminate the Period of Employment for any reason, with or
                      without cause, by providing Employer thirty (30) days'
                      advance written notice. Employer shall have the option, in
                      its complete discretion, to make termination of the Period
                      of Employment effective at any time prior to the end of
                      such notice period, provided Employer pays Executive all
                      compensation due and owing through the last day actually
                      worked, plus an amount equal to the base salary Executive
                      would have earned through the balance of the above notice
                      period. Thereafter, all of the Company's obligations under
                      this Agreement shall cease, except as otherwise provided
                      for in this Paragraph



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                      4(e). In the event Executive terminates the Period of
                      Employment pursuant to this Paragraph 4(e), the Company
                      shall pay for Executive's share of health insurance
                      premiums for Executive and his qualified dependents, in
                      accordance with the Company's existing officer retirement
                      health benefit program, as evidenced by the Company's July
                      1993 Board of Directors' Resolution Regarding Officers'
                      Retirement, Medical and Dental Coverage, without regard to
                      age or length of service limitations therein.

        8.     AGREEMENT CONTINUES. Except as specifically modified herein, the
terms and conditions of the Agreement shall remain in full force and effect.
This Amendment shall be attached to the Agreement as Exhibit A.

        9.     DEFINITIONS. Capitalized terms used herein shall have the
meanings set for the Agreement, unless otherwise specifically defined herein.

        10.    REPRESENTATION BY COUNSEL. The parties acknowledge that (a) they
have had the opportunity to consult counsel in regard to this Amendment; (b)
they have read and understand the Amendment and they are fully aware of its
legal effect; and (c) they are entering into this Amendment freely and
voluntarily, and based on each party's own judgment and not on any
representations or promises made by the other party, other than those contained
in this Amendment.

        11.    DATE OF AMENDMENT. The parties have duly executed this Amendment
as of the date first written above.


                                        ________________________________________
                                                      Richard Hill


                                        NOVELLUS SYSTEMS, INC.


                                        By: ____________________________________
                                                 Robert H. Smith
                                                 Executive Vice President




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