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                                                                   EXHIBIT 10.12


[LOGO OF ADAPTIVE BROADBAND]


                         ADAPTIVE BROADBAND CORPORATION

                              SEVERANCE AGREEMENT
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THIS SEVERANCE AGREEMENT is entered into as of March 1, 2000 (the  "Effective
Date"), between ADAPTIVE BROADBAND CORPORATION, a Delaware corporation ("ADAP")
and Kenneth Wees (the "Employee").

                                    RECITAL
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The Employee serves as ADAP's Vice president, General Counsel and Secretary.
ADAP and the Employee desire to set forth the terms of the Employee's severance
compensation if the Employee's employment is ended as a result of a Change in
Control.  If a Change in Control occurs, the Employee and other key employees
may be more vulnerable to dismissal or other negative consequences without
regard to the quality of their past or prospective service.  The Board of
Directors (the "Board") believes that it is in the best interest of ADAP and its
stockholders to ensure fair treatment to ADAP's key executives and to reduce any
adverse effects upon their performance that may be caused by the perceived risks
of a merger or acquisition.

The parties agree as follows:

1.  Definitions.  For purposes of this Agreement, the following terms will have
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    the meanings set forth below.

      1.1   A "Change in Control" will occur if (a) any Person (as defined in
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            Section 2(a)(2) of the Securities Act of 1933, as amended) other
            than ADAP, is or becomes the beneficial owner, directly or
            indirectly (including by holding securities which are exercisable
            for or convertible into shares of capital stock of ADAP), of 30 % or
            more of the combined voting power of the outstanding shares of
            capital stock of ADAP entitled to vote generally in the election of
            directors ; or, (b) ADAP sells, leases or exchanges all or
            substantially all of its property and assets under Section 271 of
            the General Corporation Law of the State of Delaware, or, (c)
            Continuing Directors cease to constitute at least a majority of the
            Board: or, (d) a majority of the ADAP's Outside Directors determine
            that a Change in Control has occurred.
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      1.2   "Continuing Directors" shall mean the directors of ADAP in office on
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            January 1, 1999 and any successor to any such director whose
            nomination or selection was approved by a majority of the directors
            in office at the time of the director's nomination or selection and
            who is not an "affiliate" or "associate" (as defined in Rule 12b-2
            under the Securities Exchange Act of 1934, as amended) of any person
            who is the beneficial owner, directly or indirectly (including by
            holding securities which are exercisable for or convertible into
            shares of capital stock of ADAP), of 10% or more of the combined
            voting power of the outstanding shares of capital stock of ADAP
            entitled to vote generally in the election of directors.

      1.3   "Disability" means that the Employee has met the qualifications for
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            ADAP's long-term disability benefit.

      1.4   "Good Reason" includes any of the following:
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            (a)  the assignment to the Employee of duties inconsistent with, or
                 a substantial alteration in the nature or status of, the
                 Employee's responsibilities immediately before a Change in
                 Control;

            (b)  a reduction in the Employee's salary or other benefits as in
                 effect on the date of a Change in Control;

            (c)  the Employee's relocation to a work site requiring an increase
                 in one-way commute from Employee's residence of more than
                 thirty-five (35) miles; or

            (d)  a breach by ADAP of this Agreement if the breach has not been
                 cured within 30 days after written notice by the Employee to
                 ADAP setting forth with specificity the nature of the breach.

      1.5   "Outside Director" is a member of ADAP's Board of Directors who is
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            not, and who during the past six months was not, an employee or
            officer of ADAP.

      1.6   "Termination for Cause" is termination of the Employee's employment
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            as a result of (a) the Employee's willful misconduct or the
            Employee's dishonesty towards, fraud upon, crime against or
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            deliberate or attempted injury or bad faith action with respect to
            ADAP; or (b) the Employee's conviction for a felony (whether in
            connection with ADAP's affairs or otherwise).

      1.7   "Termination Upon a Change in Control" is (a) termination by the
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            Employee of Employee's employment for Good Reason within one year
            after the occurrence of a Change in Control; or (b) declination by
            the Employee of an offer of employment from ADAP, or ADAP's
            successor, for Good Reason at the time of a Change in Control if the
            Employee would not have been permitted to remain in Employee's
            existing position following such declination; or (c) termination by
            ADAP, or ADAP's successor, of the Employee's employment within one
            year after the occurrence of a Change in Control other than a
            Termination for Cause or a termination resulting from the Employee's
            death or Disability.

2.  Term.  If no Change in Control has occurred, this Agreement will expire on
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    December 31, 2001. If a Change in Control occurs prior to December 31, 2001,
    this Agreement will continue in effect, and will not terminate, until either
    the Employee has received the severance compensation provided for below or
    has ceased to be eligible for such compensation by reason of there not
    having been a Termination Upon a Change in Control.

3.  Termination Upon a Change in Control.  If a Termination Upon a Change in
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    Control occurs, the Employee will immediately be paid all (a) accrued
    salary, (b) bonus or sales commission compensation equal to the higher of
    (i) the annual bonus or sales commission that would result from implementing
    ADAP's operating plan as approved by the Board during the first quarter of
    the fiscal year during which the Change in Control occurs, provided that the
    criteria which determine the bonus or sales commission payout for such
    fiscal year as of the most recently completed fiscal quarter are equal to or
    exceeding those specified in the operating plan for such period, or (ii) the
    annual bonus, sales commission or other equivalent incentive compensation
    payment established for the Employee by ADAP's successor and based on the
    operating plan of ADAP's successor at the beginning of the bonus's or sales
    commission performance period during which Employee's termination occurs,
    irrespective of the operating performance at the time of termination, (c)
    vested deferred compensation plus the value of any unvested company matching
    shares of ADAP phantom stock in the Supplemental Executive Deferred
    Compensation Plan (other than pension plan or profit sharing plan benefits,
    which will be paid in accordance with the applicable plan), unless the
    Employee is eligible for a delayed payout as authorized by the plan, (d)
    benefits then due under any plans of ADAP or ADAP's successor in which the
    Employee is a participant, (e) accrued Personal Time Off pay or vacation pay
    and (f) reimbursements for any appropriate business expenses incurred by the
    Employee in connection with his duties, all to the date of termination
    ("Accrued Compensation").
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    Repayment of any existing company loans shall be extended if necessary to
    delay repayment until the beginning of regular employment during the period
    of severance compensation provided for in Section 4. The Employee will also
    be entitled to the severance compensation described in Section 4.

4.  Severance Compensation. If a Termination Upon a Change in Control occurs,
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    ADAP or ADAP's successor shall pay weekly severance compensation to the
    Employee for a period ending 104 weeks after termination in an aggregate
    amount determined by adding (a) the Employee's weekly base salary at the
    time of termination and (b) the amount of $553.85 paid in lieu of other
    employee benefits (including health benefits) which the Employee was
    receiving from ADAP and (c) an amount equal to the monthly `Perk Pot'
    benefit to which the Employee was entitled as an officer of ADAP at the time
    of the Change in Control. If the Employee begins regular employment prior to
    the expiration of the aforesaid 104 week period, then the severance
    compensation provided for in this Section 4 shall end as of the later of (i)
    the date of such regular employment or (ii) 52 weeks after the Termination
    Upon a Change in Control. Employee agrees to promptly notify in writing the
    payer of such severance compensation if any such regular employment is
    accepted by the Employee during this period and to reimburse the payer for
    any payments made hereunder that cover any period beyond the 52 week minimum
    during which the Employee was a regular employee.

5.  Acceleration of Options.  If a Termination Upon a Change in Control occurs,
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    all stock options held by the Employee immediately before the termination
    will become fully vested and the stock options will be exercisable for the
    periods specified with respect to termination of employment in the plans
    covering the options.

6.  Other Benefits.  Neither this Agreement nor the severance compensation that
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    it provides for will reduce any amounts otherwise payable, or in any way
    diminish the Employee's rights as an employee of ADAP, whether existing now
    or hereafter, under any benefit, incentive, retirement, stock option, stock
    bonus or stock purchase plan or under any employment agreement or other plan
    or arrangement, provided, however, that the rights granted to the Employee
    and the obligations assumed by ADAP under this Agreement will be in lieu of,
    and not in addition to, any severance or other termination payments to which
    the Employee may be entitled under any employment agreement or other plan or
    arrangement that the Employee may now or hereafter have with ADAP.

7.  Employment Status.  This Agreement does not constitute a contract of
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    employment.  It does not impose on ADAP any obligation to retain the
    Employee as an employee, to change the status of the Employee's employment
    or to change ADAP's policies regarding termination of employment.

8.  Miscellaneous.
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    a.   Severability.  If a court or other body of competent jurisdiction
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         determines that any provision of this Agreement is invalid or
         unenforceable, that provision will be adjusted rather than voided, if
         possible, so that it is enforceable to the maximum extent possible, and
         all other provisions of the Agreement will be deemed valid and
         enforceable to the fullest extent possible.

    b.   Withholding.  Compensation and benefits to the Employee under this
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         Agreement will be reduced by all federal, state, local and other
         withholdings or similar taxes as required by applicable law.

    c.   Arbitration.  The parties will submit all controversies, claims and
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         matters of difference in any way related to this Agreement, its
         performance or breach, to arbitration in San Francisco, California,
         according to the rules and practices of the American Arbitration
         Association from time to time in effect. Any awards in such arbitration
         shall be final and binding on all parties. The arbitrators shall
         allocate the costs of the arbitration in such manner as they deem
         equitable. The arbitrators may require the reimbursement of all or a
         portion of the reasonable legal fees incurred by the prevailing party
         in the arbitration proceeding and any legal proceedings which are taken
         to enforce the arbitral award.

    d.   Entire Agreement: Modifications. (i) This Agreement is the entire
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         agreement between the parties with respect to the matters covered
         hereby, and may be amended, modified, superseded or canceled, or its
         terms waived, only by a written instrument executed by each party or,
         in the case of a waiver, by the party waiving compliance. (ii) Failure
         of a party at any time to require performance of any provision of this
         Agreement will not affect the right at a later time to enforce the
         same. (iii) No waiver of a breach of this Agreement, whether by conduct
         or otherwise, in any one or more instances will be construed as a
         further or continuing waiver of the breach or of any other term of this
         Agreement. (iv) This Agreement shall inure to the benefit of and be
         binding upon the successors and assigns of the parties hereto.

    e.   Applicable Law. This Agreement will be construed under and governed by
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         the laws of the State of California without regard or reference to the
         rules of conflicts of law that would require the application of the
         laws of any other jurisdiction.

9.       Prior Severance Agreement.  The Employee and ADAP acknowledge their
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         prior severance agreement dated July 2, 1999. The Employee and ADAP
         hereby terminate such prior severance agreement as of the day
         immediately prior to the Effective Date of this Agreement, and neither
         the Employee nor ADAP shall have any rights or obligations thereunder.
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IN WITNESS WHEREOF, the parties have executed this Agreement as of the day and
year first above written.

ADAPTIVE BROADBAND, INC.


<TABLE>
<S>                                               <C>
/s/ Frederick D. Lawrence
______________________________________            _________________________________________________
Frederick D. Lawrence                             Kenneth Wees
Chairman and Chief Executive Officer              Vice President, General Counsel and
                                                  Secretary
</TABLE>