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                                                                   EXHIBIT 10.18

                      AMENDED AND RESTATE PROMISSORY NOTE

     Borrower:      Remedy Corp.
                    1505 Salado Drive
                    Mountain View, CA 94043

     Lender:        Silicon Valley Bank
                    3003 Tasman Drive
                    Santa Clara, CA 95054

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           Principal Amount: $15,000,000.00     Initial Rate: 8.500%
                          Date of Note: June 15, 1997

PROMISE TO PAY. Remedy Corp. ("Borrower") promises to pay to Silicon Valley
Bank ("Lender"), or order, in lawful money of the United States of America, the
principal amount of Fifteen Million & 00/100 Dollars ($15,000,000.00) or so
much as may be outstanding, together with interest on the unpaid outstanding
principal balance of each advance. Interest shall be calculated from the date
of each advance until repayment of each advance.

PAYMENT. Borrower will pay this loan in one payment of all outstanding
principal plus all accrued unpaid interest on June 14, 1998. In addition,
Borrower will pay regular monthly payments of accrued unpaid interest beginning
July 14, 1997, and all subsequent interest payments are due on the same day of
each month after that. Interest on this Note is computed on a 365/360 simple
interest basis; that is, by applying the ratio of the annual interest rate over
a year of 360 days, multiplied by the outstanding principal balance, multiplied
by the actual number of days the principal balance is outstanding. Borrower
will pay Lender at Lender's address shown above or at such other place as
Lender may designate in writing. Unless otherwise agreed or required by
applicable law, payments will be applied first to accrued unpaid interest, then
to principal, and any remaining amount to any unpaid collection costs and late
charges.

VARIABLE INTEREST RATE. The interest rate on this Note is subject to change
from time to time based on changes in an index which is Lender's Prime Rate
(the "Index"). This is the rate the Lender charges, or would charge, on 90-day
unsecured loans to the most creditworthy corporate customers. This rate may or
may not be the lowest rate available from Lender at any given time. Lender will
tell Borrower the current Index rate upon Borrower's request. Borrower
understands that Lender may make loans based on other rates as well. The
interest rate change will not occur more often than each time the prime rate is
adjusted by Silicon Valley Bank. The Index currently is 8.500% per annum. The
interest rate to be applied to the unpaid principal balance of this Note will
be at a rate equal to the Index, resulting in an initial rate of 8.500% per
annum. NOTICE: Under no circumstances will the interest rate on this Note be
more than the maximum rate allowed by applicable law.

PREPAYMENT. Borrower may pay without penalty all or a portion of the amount
owed earlier than it is due. Early payments will not, unless agreed to by
Lender in writing, relieve Borrower of Borrower's obligation to continue to
make payments of accrued unpaid interest. Rather, they will reduce the
principal balance due.

DEFAULT. Borrower will be in default if any of the following happens: (a)
Borrower fails to make any payment when due. (b) Borrower breaks any promise
Borrower has made to Lender, or Borrower fails to comply with or to perform
when due any other term, obligation, covenant, or condition contained in this
Note or any agreement related to this Note, or in any other agreement or loan
Borrower has with Lender, specifically that Amended and Restated Business Loan
Agreement and Negative Pledge Agreement, both of even date herewith. (c)
Borrower defaults under any loan, extension of credit, security agreement,
purchase or sales agreement, or any other agreement, in favor of any other
creditor or person that may materially affect any of Borrower's property or
Borrower's ability to repay this Note or perform Borrower's obligations under
this Note or any of the Related Documents. (d) Any representation or statement
made or furnished to Lender by Borrower or on Borrower's behalf is knowingly
false or misleading in any material respect either now or at the time made or
furnished. (e) Borrower becomes insolvent, a receiver is appointed for any part
of Borrower's property, Borrower makes an assignment for the benefit of
creditors, or any proceeding is commenced either by Borrower or against
Borrower under any bankruptcy or insolvency laws. (f) Any creditor tries to
take any of Borrower's property on or in which Lender has a lien or security
interest. This includes a garnishment of any of Borrower's accounts with
Lender. (g) Any guarantor dies or any of the other events described in this
default section occurs with respect to any guarantor of this Note. (h) A
material adverse change occurs in Borrower's financial condition, or Lender
believes the prospect of payment or performance of the Indebtedness is
impaired.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, without
notice, and then Borrower will pay that amount. Upon Borrower's failure to pay
all amounts declared due pursuant to this section, including failure to pay
upon final maturity, Lender, at its option, may also, if permitted under
applicable law, do one or both of the following: (a) increase the variable
interest rate on this Note to 5.000 percentage points over the Index, and (b)
add any unpaid accrued interest to principal and such sum will bear interest
therefrom until paid at the rate provided in this Note (including any increased
rate). Lender may hire or pay someone else to help collect this Note if
Borrower does not pay. Borrower also will pay Lender that amount. This
includes, subject to any limits under applicable law, Lender's attorneys' fees
and Lender's legal expenses whether or not there is a lawsuit, including
attorneys' fees and legal expenses for bankruptcy proceedings (including
efforts to modify or vacate any automatic stay or injunction), appeals, and any
anticipated post-judgment collection services. Borrower also will pay any court
costs, in addition to all other sums provided by law. This Note has been
delivered to Lender and accepted by Lender in the State of California. If there
is a lawsuit, Borrower agrees upon Lender's request to submit to the
jurisdiction of the courts of Santa Clara County, the State of California.
Lender and Borrower hereby waive the right to any jury trial in any action,
proceeding, or counterclaim brought by either Lender or Borrower against the
other. (Initial Here  [INITIALS] ) This Note shall be governed by and construed
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in accordance with the laws of the State of California.

LINE OF CREDIT. This Note evidences a revolving line of credit. Advances under
this Note, as well as directions for payment from Borrower's accounts, may be
requested orally or in writing by Borrower or by an authorized person. Lender
may, but need not, require that all oral requests be confirmed in writing.
Borrower agrees to be liable for all sums either: (a) advanced in accordance
with the instructions of an authorized person or (b) credited to any of
Borrower's accounts with Lender. The unpaid principal balance owing on this
Note at any time may be evidenced by endorsements on this Note or by Lender's
internal records, including daily computer print-outs. Lender will have no
obligation to advance funds under this Note if: (a) Borrower or any guarantor
is in default under the terms of this Note or any agreement that Borrower or
any guarantor has with Lender, including any agreement made in connection with
the signing of this Note; (b) Borrower or any guarantor ceases doing business
or is insolvent; (c) any guarantor seeks, claims or otherwise attempts to
limit, modify or revoke such guarantor's guarantee of this Note or any other
loan with Lender; or (d) Borrower has applied funds provided pursuant to this
Note for purposes other than those authorized by Lender.

REQUEST TO DEBIT ACCOUNTS. Borrower will regularly deposit funds received from
its business activities in accounts maintained by Borrower at Silicon Valley
Bank. Borrower hereby requests and authorizes Lender to debit any of Borrower's
accounts with Lender, specifically, without limitation, Account Number
02-732084-70, for payments of principal and interest due on the loan and any
other obligations owing by Borrower to Lender. Lender
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                      AMENDED AND RESTATED PROMISSORY NOTE
                                     PAGE 2


will notify Borrower of all debits which Lender makes against Borrower's
accounts. Any such debits against Borrower's accounts in no way shall be deemed
a set-off.

AMENDED AND RESTATED BUSINESS LOAN AGREEMENT. This Note is subject to and shall
be governed by all the terms and conditions of the Amended and Restated
Business Loan Agreement of even date herewith, between Lender and Borrower, as
such agreement may be amended from time to time, which Business Loan Agreement
is incorporated herein by reference.

AMENDMENT AND RESTATEMENT. This Amended and Restated Promissory Note amends and
restates the terms and conditions of the obligations of Borrower under that
certain Promissory Note dated January 4, 1993, as amended (the "Original Note")
from Borrower to Lender. Nothing contained in this Amended and Restated
Promissory Note shall be deemed to create or represent the issuance of new
indebtedness or exchange by Borrower of the Original Note for a new Promissory
Note.

GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them. Borrower and any other person who
signs, guarantees or endorses this Note, to the extent allowed by law, waive
any applicable statute of limitations, presentment, demand for payment,
protest and notice of dishonor. Upon any change in the terms of this Note, and
unless otherwise expressly stated in writing, no party who signs this Note,
whether as maker, guarantor, accommodation maker or endorser, shall be released
from liability. All such parties agree that Lender may renew or extend
(repeatedly and for any length of time) this loan, or release any party or
guarantor or collateral; or impair, fail to realize upon or perfect Lender's
security interest in the collateral; and take any other action deemed necessary
by Lender without the consent of or notice to anyone. All such parties also
agree that Lender may modify this loan without the consent of or notice to
anyone other than the party with whom the modification is made.

PRIOR TO SIGNING THIS NOTE, BORROWER HAS READ AND UNDERSTOOD ALL THE PROVISIONS
OF THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISION. BORROWER AGREES
TO THE TERMS OF THE NOTE AND ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THE
NOTE.

BORROWER:
Remedy Corp.

By:     /s/ GEORGE A. DE URIOSTE
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        George A. de Urioste
Name: ---------------------------------

Title:  Vice President, Finance and
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        Chief Financial Officer