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                                                                   Exhibit 10.15

                             STOCK OPTION AGREEMENT

THIS AGREEMENT is made and entered into this        day of               ,1995
by and between TOLLGRADE COMMUNICATIONS, INC., a Pennsylvania corporation (the
"Company") and (the "Holder").

WHEREAS, the Company desires to issue, and the Holder desires to receive,
Options to purchase shares of the common stock of the Company, pursuant to the
terms described herein.

NOW, THEREFORE, in consideration of the terms and conditions contained herein
and intending to be legally bound hereby, the parties agree as follows:

   1. Grant of Option.  The Company hereby grants to Holder the right, privilege
and option to purchase at any time prior to      up to     shares of fully paid 
and nonassessable no par value common stock of the Company, at a purchase price 
of         per share (the "Option"), upon written request by the Holder at the
office of the Transfer Agent for the Company, or if there be none, at the
principal office of the Company at 493 Nixon Road, Cheswick, Pennsylvania
15025 and upon payment of the purchase price appropriate thereto.

   2. Investment Purpose. The Holder represents to the Company that such Holder
is acquiring this Option and any securities which may be acquired pursuant to
this Option for investment and not with a view to or for sale in connection
with any distribution thereof. Such Holder represents that he will not sell or
transfer any securities acquired pursuant to this Option in violation of the
Securities Act of 1933, as amended (the "Act"), or the rules and regulations
promulgated thereunder. Without limiting the scope of the foregoing
representation and warranty, the Holder agrees that he will not sell or
transfer any such securities unless either (I) a Registration Statement under
the Act shall be in effect with respect to such


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securities and the Holder shall comply with the provisions of the Act in
connection with the sale of such securities or (ii) the Holder has, prior to any
transfer or attempt to transfer such securities, obtained an opinion of counsel
to the Company to the effect that in the opinion of such counsel, such transfer
may be effected without registration of such securities under the Act.

   3. Legend. The Holder of this Option agrees that the Company may place a
legend reflecting the provision of the foregoing paragraph on each certificate
evidencing any securities delivered to the Holder pursuant to this Option and
the Company may refuse to transfer on its books any such securities which the
Holder may attempt to transfer otherwise then in compliance herewith.

   4. Recapitalization. (a) Subject to any required action by the stockholders,
the number of shares of common stock of the Company covered by this Option, and
the price per share thereof, shall be proportionately adjusted for any increase
or decrease in the number of issued shares of common stock of the Company
resulting from the subdivision of consolidation of shares or the payment of
stock dividend (but only on the common stock of the Company covered by this
Option) or any other increase or decrease in the number of such shares affected
without receipt of consideration by the Company. Subject to any required action
by the stockholders, if the Company shall be the surviving company in any
merger or consolidation, this Option shall pertain to and apply to the
securities to which a holder of the number of shares of common stock of the
Company subject to the Option would have been entitled. A dissolution or
liquidation of the Company or a merger or consolidation in which the Company is
not the surviving company shall cause this Option to terminate, provided that
the Holder shall, in such event, have the right immediately prior to such
dissolution or liquidation or merger or consolidation in which the Company is
not the surviving company, to exercise his Option in whole or in part.

(b) Except as hereinbefore expressly provided, the Holder shall have no rights
by reason of any subdivision or consolidation of shares of stock of any class
or the payment of any stock dividend or other increase or decrease in the
number of shares of stock of any class or by reason of any dissolution,
liquidation, merger or consolidation or spin-off of assets or stock of another
company, and any issue by the Company of shares of stock of any class, or
securities convertible into shares of stock of any class, shall not affect, and
no


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adjustment by reason thereof shall be made with respect to, the number or
price of shares of common stock subject to the Option.

   5. Fractional Shares.  No fractional shares of common stock will be issued in
connection with any subscription hereunder, but in lieu of such fractional
shares, the Company shall make a cash payment thereof upon the basis of the
Option price then in effect.

   6. Non-Transferability.  This Option is nontransferable except pursuant to
the laws of succession and descent.

   7. Reservation of Shares. The Company covenants that during the period this
Option is exercisable, the Company will reserve from its authorized and
unissued common stock a sufficient number of shares to provide for the issuance
of common stock upon the exercise of this Option.

   8. Indemnification. The Holder indemnifies and holds harmless the Company
against any and all loss, damages, liability or expense, including costs and
reasonable attorneys' fees to which they may be put or which they may incur by
reason of or in connection with any misrepresentation made by the Holder, any
breach of any of his warranties, or his failure to fulfill any of his covenants
or agreements set forth herein. The Option and the representations and
warranties contained herein shall be binding upon the heirs, legal
representatives and successors of the undersigned.

   9. Exercise of Option. This Option may be exercised by the Holder, in
whole or in part, by the surrender of this Option at the principal office of
the Company. Upon partial exercise hereof, a new Option or Options containing
the same provisions as this Option shall be issued by the Company to Holder for
the number of shares of common stock with respect to which this Option shall
not have been exercised.

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HOLDER                                       TOLLGRADE COMMUNICATIONS, INC.

                                             By:
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                                             ATTEST:

                                             By:
                                                -----------------------------

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