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                                                                   EXHIBIT 4.2

                SECOND AMENDMENT TO THE SPECTRANETICS CORPORATION
                          EMPLOYEE STOCK PURCHASE PLAN


         This Second Amendment to The Spectranetics Corporation Employee Stock
Purchase Plan (the "Amendment") is adopted by the Board of Directors of The
Spectranetics Corporation, a Delaware corporation (the "Company"), effective as
of June 21, 2000.

                                    RECITALS

         I. The Company's Employee Stock Purchase Plan (the "Plan") was adopted
by the Board of Directors of the Company (the "Board") on September 15, 1992,
and approved by the stockholders on September 15, 1993. The Company's First
Amendment to the Plan was approved by the Board on December 29, 1994, and
approved by the stockholders on June 12, 1995.

         II. The Board desires to amend the Plan to (i) increase the number of
shares of the Company's common stock which may be sold to employees thereunder
from 350,000 to 850,000, and (ii) increase the maximum percentage of a
participant's base compensation which may used to purchase stock in a particular
purchase period from 5% to 15%.

         III. Effective as of April 25, 2000, the Board of Directors unanimously
adopted the Amendment in the form given below, subject to approval of the
Amendment by the Company's stockholders.

                                    AMENDMENT

         A. Section V(a) of the Plan is hereby amended and restated in its
entirety to read as follows:

                  "(a) Common Stock. The stock which is purchasable by
         Participants shall be the Company's authorized but unissued or
         reacquired Common Stock, par value $.001 per share (the "Common
         Stock"). In order to have shares available for sale under the Plan, the
         Company may repurchase shares of Common Stock on the open market or
         otherwise. The maximum number of shares which may be sold to employees
         during any single purchase period shall be established by the Committee
         prior to the beginning of the purchase period, provided however, that
         the total number of shares which may be sold to employees throughout
         the entire duration of the Plan shall not exceed 850,000 shares
         (subject to adjustment under subparagraph (b) below)."

         B. Section VI(c)(i) of the Plan is hereby amended and restated in its
entirety to read as follows:

                  "(i) The maximum percentage of a Participant's Base
         Compensation which may be paid for the purchase of stock in a
         particular purchase period shall be fifteen percent (15%); provided,
         however, that the Committee may establish prior to the beginning of the
         purchase period a maximum number of shares (subject to adjustment under
         Section V(b)) that may be purchased during the purchase period by each
         Participant."

         C. This Amendment shall be and is hereby incorporated in and forms a
part of the Plan.

         D. All other terms and provisions of the Plan shall remain unchanged
except as specifically modified herein.

         E. The Plan, as amended by this Amendment, is hereby ratified and
confirmed.


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         The undersigned, Guy A. Childs, Assistant Secretary, hereby certifies
that the Board of Directors of the Company adopted the foregoing Amendment as
stated in Recital III above.

         Executed at Colorado Springs, Colorado this 25th day of April 2000.


                                           /s/ Guy A. Childs

                                           Guy A. Childs, Assistant Secretary