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                                                                 EXHIBIT 10.13B

                                  June 10, 1997

Mr. Ronald J. Clear
3700 Ocean Boulevard
Corona Del Mar, CA  92625

         Re: Agreement for Services

Dear Ron:

         When executed by you and a duly authorized representative of
ParcPlace/Digitalk, Inc. (the "Company"), this letter will set forth the
agreement (the "Agreement") reached between you and the Company with regard to
your employment.

                  Term of Employment. The initial term of this Agreement shall
be for a period of six (6) months commencing on June 10, 1997 and continuing
until the six (6) month anniversary of such commencement date. If, during this
initial term, the Company terminates your employment for any reason other than
"Cause", as hereinafter defined, you shall be entitled to receive an amount
equal to the remaining unpaid compensation for such six (6) month period,
payable in a lump sum at the time of such termination. After the initial six
month term, your employment shall continue for an indefinite period, terminable
by either party (with or without cause) upon giving not less than ninety (90)
days written notice of such termination to the other party. If the Company
terminates your services upon less than ninety (90) days notice (unless for
Cause), you shall be entitled to compensation for the entire ninety (90) day
period, payable in a lump sum at the time of such termination. For the purpose
of this Agreement, "Cause" shall mean conviction of a felony, actions on your
part involving fraud or dishonesty which are intended to result in your material
personal enrichment at the expense of the Company, or repeated willful
violations of specific directions to you from the Company's board of directors
and which have not been cured by you within a reasonable time after written
notice to you specifying the nature of such violations.

                  Title and Duties. You will be employed by the 



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Company as Vice President and Chief Financial Officer. You shall use your best
efforts to promote the business and affairs of the Company, and shall discharge
your responsibilities in a diligent and faithful manner, consistent with sound
business practices.

         Compensation.

                  Base Salary. Subject to all customary withholding and other
deductions as may be required by applicable laws, Clear Alexander & Associates
will be compensated at an annual rate of One Hundred Sixty Thousand Dollars
($175,000), to be reviewed on each anniversary of employment at the discretion
of the Company.

         (b) Discretionary Bonus. During the term hereof, you will be eligible
to receive a discretionary bonus at the discretion of the Board of Directors.

         Benefits.

                  Medical and Other Benefits. As you become eligible for them,
you will be entitled to receive from the Company those medical, dental and
related benefits which are currently available to the Company's CEO. You agree
that nothing contained in the Agreement shall prevent the Company from changing
insurance carriers or from effecting modifications to or eliminating such
benefits entirely. You will also receive all other benefits to which the
Company's current CEO is entitled.

                 Stock Options. Subject to the terms and conditions of the terms
of a written stock option agreement to be entered into between you and the
Company, the Company shall grant to you an option (the "Option") to acquire one
hundred ninety five thousand (195,000) shares of the Company's common stock (the
"Option Shares"), at a purchase price per share equal to the closing price of a
share of the Company's common stock on the NASDAQ Stock Market on the date
hereof, as reported by The Wall Street Journal. The Option shall vest with
respect to 65,000 Option Shares six (6) months from the date hereof, and 32,500
Option Shares on each three (3) month anniversary date thereafter. In addition,
all of the Option Shares shall vest on an accelerated basis immediately prior to
(i) the dissolution or liquidation of



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the Company, (ii) the reorganization, merger or consolidation of the Company
with or into one or more other corporations, (iii) the sale of a majority of the
Company's assets in connection with the distribution of the sales proceeds
therefrom to the stockholders of the Company, or (iv) the acquisition by any
person or entity, or group of affiliated persons or entities, of equity
securities of the Company representing thirty percent (30%) or more of the
aggregate voting power of all outstanding securities of the Company. Your
options shall cease further vesting upon the cessation of your employment by the
Company. Notwithstanding the foregoing, in the event the Company terminates your
employment for other than Cause, then with your and the Company's consent (which
consents will not be unreasonably withheld), you shall serve as an advisor to
the Company, and your options will continue to vest, for a period of eighteen
(18) months following the date hereof (at which time your options shall be fully
vested). Such advisory services shall be on a part time/occasional basis and,
unless otherwise agreed to by the Company, you will not be entitled to
compensation for such advisory work. The Company shall file a Registration
Statement on Form S-8 registering the shares underlying the option with the SEC
and file with the Nasdaq Stock Market a supplemental listing application for
such shares within sixty days from the date of this letter. Your Stock Options
shall have a five (5) year term. In the event your employment with the Company
ceases for any reason, you will have three (3) years to exercise any vested
Option Shares.

                  Reimbursable Expenses. Subject to your furnishing to the
Company adequate records and other documentary evidence, the Company shall
reimburse you for all reasonable travel and business expenses incurred by you in
carrying out your duties hereunder at either office located in California.

                  Confidentiality. You agree to sign the Company's standard form
confidentiality agreement.

                  Waiver and Modification. No provision hereof may be waived or
modified unless in writing and signed by both parties hereto. Waiver of any one
provision herein shall not be deemed to be a waiver of any other provision
herein.

                  Entire Agreement. Except as set forth in Sections 4(b) and 6
herein, this Agreement contains the sole and 


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entire agreement between the parties and supersedes all prior oral and written
agreements, understandings, statements and practices between the parties.

                  Arbitration. Any dispute arising out of this agreement or your
employment by the Company shall be resolved by binding arbitration with
JAMS/Endispute. The prevailing party shall be entitled to recover his/its
reasonable attorneys' fees and costs.

         If the foregoing accurately sets forth your understanding as to the
terms of your services, please sign and return the enclosed copy of this letter.

                                     PARCPLACE/DIGITALK, INC.



                                     By: /s/ PARCPLACE-DIGITALK, INC.
                                        --------------------------------

AGREED AND ACCEPTED:


/s/ RONALD J. CLEAR
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Ronald J. Clear