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                                                                  EXHIBIT 10.21

                                       
                  ENGINEERING AND SPECTRUM MANAGEMENT AGREEMENT

     ENGINEERING AND SPECTRUM MANAGEMENT AGREEMENT (this "Agreement"), dated 
as of the 1ST day of MARCH, 1999, by and among CS Wireless Systems, Inc. 
("Company"), a Delaware corporation having a place of business at 1101 Summit 
Avenue,  Plano, TX 75074, CAI Wireless Systems, Inc. ("CAI"), a Connecticut 
corporation, having a place of business at 18 Corporate Woods Boulevard, 
Albany New York and CAI/AMI Spectrum Management, Inc. ("AMI" or "Manager"), a 
Delaware corporation and wholly owned subsidiary of CAI, having a place of 
business at 2101 Wilson Boulevard, Suite 100, Arlington, VA 22201.

     WHEREAS, the Company desires to continue to expand the uses to which the
microwave radio frequencies, including without limitation MMDS, MDS, ITFS and
WCS spectrum under its control ("Spectrum" as further defined below) can be put,
in order to maximize the value of the Spectrum and perform its obligations under
the terms of various frequency leases;

     WHEREAS, the Federal Communications Commission has approved the grant of
broad authority for flexible two-way use of the Spectrum in a digital format
pursuant to complex procedures that require significant engineering effort
("Two-Way Authority", as further defined below);

     WHEREAS, the Company does not have the experienced personnel that would
allow it to pursue and take advantage of the Two-Way Authority within the
earliest filing periods contemplated by the FCC orders authorizing Two-Way
Authority and has concluded that it would not be possible to hire such
experienced personnel or to arrange for such work to be conducted by unrelated
contractors except at significant expense to the Company, if at all;

     WHEREAS, AMI has experienced engineering/licensing capability, directly and
through affiliated and unaffiliated third parties, and because of the extensive
work done by its personnel to date, has substantial experience with respect to
the industry, the FCC and the specific Business Plan (defined herein) of the
Company;

     WHEREAS, CAI is engaged in the development of its Spectrum in a manner
contemplated by the Business Plan and directly and through AMI has significant
experience in the industry and has had extensive contact with potential
strategic users of the Spectrum; 

     WHEREAS, CAI and the Company believe that by coordinating their Two Way
Authority efforts and by combining the access to their Spectrum through a single
plan engineered and managed by AMI personnel as a single cohesive platform
across their respective markets, the Company is more likely to achieve the goals
reflected in the Business Plan or otherwise maximize the value of its Spectrum
for all of its stakeholders;
     
     WHEREAS, CAI is prepared to incorporate the Company's Spectrum and Markets
in the arrangements it is discussing with potential strategic investors on the
terms herein set forth and to make AMI's services available to the Company
substantially on a pro rata cost plus 

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administrative fee basis; 

     WHEREAS, AMI is prepared to assume the engineering and licencing functions
of the Company and to undertake to assume all responsibility for applications
and negotiations for Two-Way Authority, subject to the terms and conditions
hereinafter set forth; 

     WHEREAS, Company previously retained CAI to perform certain engineering
services pursuant to that certain Engineering Services Agreement dated as of
March __, 1998, to which CAI is not prepared to continue to devote resources and
which, in any event, did not provide the Company sufficiently comprehensive
services to be able to complete its filings for Two Way Authority in accordance
with its Business Plan and maintain and enhance the value of its Spectrum; 

     WHEREAS, Company and CAI terminated the Engineering Services Agreement, and
the Company and Manager are prepared to establish a comprehensive contractual
relationship whereby Manager will provide various managerial, operational and
engineering services to Company for the benefit of Company and its stakeholders;
and

     WHEREAS, Company, the Manager and CAI intend that this Agreement shall set
forth the terms and conditions of the comprehensive contractual relationship of
the parties and effect the termination of the Engineering Services Agreement.
     
     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Manager, CAI and Company hereby
agree as follows:

                                     ARTICLE 1
                                    DEFINITIONS

     1.1  The following terms shall have the meanings assigned below:

     (a)  "Approved Budget" means the budget appended to the Business Plan.

     (b)   "Business Plan" means the joint Business Plan of the Company and CAI
for the development of their Spectrum, as approved by the Board of Directors of
the Company, and attached as Exhibit A1/2 to this Agreement no later than March
9, 1999, together with the five (5) year budget attached thereto, which shall
include the associated budget for the Two Way Authority and for the estimated
cost of the services hereunder, together with such amendments thereto as may be
approved by majority vote of the independent directors of each of the Company
and CAI. 

     (c)  "Spectrum Rights" means MMDS/MDS/ITFS and WCS bandwidth leased,
licensed, or otherwise controlled by the Company.

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     (d)  "Market" means any geographic area in which the Company or CAI, as the
case may be, has Spectrum Rights, at any time during the term of this Agreement.

     (e)  "FCC" means the Federal Communications Commission and its staff.

     (f)  "Analog Video and One Way Internet Operations" means the business of
the Company in providing retail video service and, where applicable, Internet
delivery telephone return/services to the public, and related support services,
including video analog engineering,  call center operations, installation and
similar services including such services provided by independent contractors.

     (g)  "Fully Allocated Cost of Performance" has the meaning set forth in 
SECTION 3.1(B)  hereof.


     (h)  "AMI Personnel Costs"  has the meaning set forth in SECTION 3.1(B) 
hereof.

     (i)  "AMI Office Rent Expenses" has the meaning set forth in  SECTION
3.1(A)  hereof.

     (j)  "AMI Equipment Expense" has the meaning set forth in  SECTION 3.1(B) 
hereof.

     (k)  "Operational Management Services" has the meaning set forth in SECTION
2.6 hereof.

     (l)  "Engineering/Spectrum Management Contract Price" has the meaning set
forth in SECTION 3.1(A)  hereof.

     (m)  "CAI Personnel Costs" shall be the full cost of a CAI employee,
including, without limitation, such employee's base salary, cash bonus (not to
exceed 20% of base salary), retirement and health and welfare benefits and all
associated taxes and withholdings, but excluding any equity-based compensation.
     
                                     ARTICLE 2
              OBLIGATIONS OF THE PARTIES WITH RESPECT TO THE SPECTRUM 

     2.1  GENERALLY.  Subject to the terms and conditions provided for herein,
each of the parties hereto shall assume the responsibilities and obligations set
forth below and hereby covenants and agrees to take the actions consistent with,
or to refrain from taking action inconsistent with, meeting such
responsibilities and obligations all as set forth herein.

     2.2  ENGINEERING/SPECTRUM MANAGEMENT SERVICES.   

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     (a)  GENERAL.  Manager shall furnish, or otherwise arrange for, manage and
supervise, all engineering and technical advice, services and consulting
relating to the organization, transmission and/or delivery of (i) wireless
cable, (ii) voice, video and data delivery and/or access and (iii) telephony
services in each of the Company's Markets.  The Manager shall formulate for and
on behalf of the Company, a plan for each of the Company's Markets to overlay
the Company's existing platform, which plan shall be engineered to address
interference and functionality issues, and shall, to the fullest extent
possible, be uniform among the Company's Markets and the Markets of CAI, so as
to facilitate access by one or more strategic users of the bandwidth represented
by the Spectrum Rights across all Markets of the two companies.  

     (b)  SPECTRUM MANAGEMENT SERVICES.  Manager shall act for and on behalf 
of the Company in all matters relating to the ownership, acquisition, 
disposition, maintenance and operation of the Spectrum, subject to the terms 
of this Agreement and, if necessary, under applicable law, to the approval of 
the Company's Board of Directors.  Manager shall be responsible for the 
planning and presentations to the Company's Board of Directors and senior 
management (as required hereunder and as may be required under applicable 
law) and any proposals relating to the acquisition, disposition, maintenance, 
and operation of the Company's Spectrum that vary from the Business Plan.  
Manager shall maintain a Licensing Committee, which shall be comprised of 
Gerald Stevens-Kittner, Steve Moncrieff and Derwood Edge and/or such 
additional or different members as it shall reasonably determine appropriate 
after consultation with the Company's Board of Directors.

     2.3  FULL DELEGATION OF AUTHORITY TO MANAGER.  The Company hereby delegates
to the Manager all authority necessary to act in its name and place for all
purposes of dealing with the FCC and any other governmental agency or body, and
with respect to any licensee of Spectrum with which the Company has a lease or
other contractual relationship or with which the Company may enter into a lease
or other contractual relationship during the term hereof, with respect to the
subject matter of this Agreement.  Without limiting the generality of the
foregoing, the Manager shall have full discretion (subject to such approvals as
may be required of the Company's Board of Directors under applicable law) in
negotiating or renegotiating all leases or other contracts for Spectrum Rights,
including all terms thereof, the filing of all applications, formulating
strategies and designing engineering and related plans and such discretion shall
be absolute; provided, however, that such discretion shall be exercised only in
good faith in furtherance of the Company's Business Plan.   Notwithstanding the
foregoing, the Manager shall not have the authority to increase the amounts
payable to any lessor under a lease for Spectrum Rights or to enter into a new
lease of Spectrum Rights on behalf of the Company, which increase or new lease
requires payments in excess of 3% of the amounts assumed in the Business Plan or
the Approved Budget.  Manager and Company agree that Manager shall have the sole
discretion in determining the scope of the services appropriate in any
particular Market at any particular time and, recognizing that applications and
related work will not occur simultaneously in all Markets, that Manager shall
determine in its sole 

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discretion, consistent with the Business Plan, the order in which the Markets 
shall be engineered, the timetable for completing the necessary work, the 
scope of the work in the particular Market and whether and to what extent 
work in a particular Market may be delayed or accelerated.  The Manager shall 
be responsible for coordinating all communicationswith the FCC and the 
Company agrees that it shall not interfere or otherwise deal with any of the 
matters under the authority of the Manager during the term of this Agreement, 
except for such action as Company must take to preserve the value of its 
assets for its stakeholders.  Manager shall have full discretion in 
determining which services shall be conducted by its own personnel and which 
services, if any, shall be performed by independent contractors retained by 
Manger on its own behalf or on behalf of the Company, subject to the 
parameters set forth in the Business Plan or the Approved Budget.   The 
Company acknowledges that the work product of the Manager is its exclusive 
proprietary information and that the Company shall not have access to any 
such work product nor the right to share or exploit such work product in any 
Market without the prior written consent of the Manager, beyond the uses 
necessary to implement the Business Plan in the particular Market. 

     2.4  ARRANGEMENTS FOR WHOLESALE/RETAIL USE OF THE SPECTRUM.  The Company
hereby delegates irrevocably to CAI and to AMI during the term of this Agreement
the right and authority to act in its stead in respect of the use of its
Spectrum for any commercial purpose consistent with the Business Plan, subject
to such approvals as may be required of the Company's Board of Directors under
applicable law.  CAI and AMI covenant and agree that if and to the extent the
Company's Spectrum is included in any arrangement with one or more third
parties, the arrangements involving the Company's Spectrum shall be no less
favorable than the arrangements entered into by CAI with respect to its
Spectrum, except where such modified arrangement is due to factors that are not
present in the case of the CAI Spectrum and such modification has been approved
by a majority of the independent members of the Board of Directors of the
Company.  The Company shall be bound by the terms of any agreement entered into
on its behalf hereunder by Manager or CAI with third parties for the duration of
such agreements, without regard to the expiration of the term of this Agreement.

     2.5  ACTING CEO SERVICES.  During the term of this Agreement, Manager shall
provide executive management services to the Company, which services shall
consist of oversight of the Company's strategic direction, including the
development and implementation of the Business Plan and the provision of an
acting chief executive officer ("CEO") who shall initially be Jared E.
Abbruzzese.  The individual named to serve as CEO herein shall not be replaced,
nor have his responsibilities or authority reduced, absent prior written
approval of a majority of the independent members of the Board of Directors of
the Company.

     2.6  OPERATIONAL MANAGEMENT SERVICES.  During the term of this Agreement,
Manger shall provide supervisory services with respect to the Company's Analog
Video and One-Way Internet Operations.  Supervisory services shall consist of
oversight of all of the Company's operations and the provision of an acting
chief operating officer ("COO") who shall initially be Derwood Edge, and which
COO shall provide operational management 

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services to the Company (collectively, the "Operational Management 
Services").  The individual named herein to serve as COO shall not be 
replaced, nor have his responsibilities or authority reduced, absent prior 
written approval of a majority of the independent members of the Board of 
Directors of the Company.

     2.7  EMPLOYEES.   All personnel assigned by Manager to perform Services
will be employees of Manager and Manager will pay all salaries and expenses of
and all federal, social security, federal and state unemployment taxes, and any
other payroll or withholding taxes relating to such employees.  Manager will be
considered, for all purposes, an independent contractor, and it will not,
directly or indirectly, act as an agent, servant or employee of the Company, or
make any commitments or incur any liabilities on behalf of Company without its
prior written consent (except that nothing herein shall be interpreted to
restrict the rights of the Manager and CAI delegated pursuant to Sections 2.3
and 2.4 hereof).  

     2.8  STANDARD OF CARE.    Manager shall perform the Services with the same
degree of care, skill and prudence customarily exercised by it in respect of its
own business operations and affairs, which standards shall be in accordance with
the standards generally applicable in the MMDS industry.

     2.9  INFORMATION.    Company will provide Manager with complete access to
all the Company's facilities and to all information and data deemed by Manager
to be necessary for Manager to provide the Services described herein and such
other information that Manager may require to perform its services under this
Agreement.  Manager shall be entitled to rely upon the accuracy and completeness
of all information that it reasonably believes to have been furnished to it by
Company or at Company's direction, and shall have no duty to inquire about such
information.  Company shall fully cooperate with the Manager.

     2.10 EXCLUSIVE RELATIONSHIP.  During the term of this Agreement, Manager
shall have the exclusive authority to act on behalf of the Company with respect
to the Spectrum and the Company shall not engage any other person to act for or
on its behalf in respect thereof without the prior written consent of the
Manager, which shall not be unreasonably withheld, conditioned or delayed.

                                      ARTICLE 3
                                   TERMS OF PAYMENT

     3.1  ENGINEERING/SPECTRUM MANAGEMENT SERVICES CONTRACT PRICE.

     (a)  CONTRACT BASE PRICE.  In consideration of the Services described in
ARTICLE 2 above, the Company shall pay to the Manager at the times set forth in
this ARTICLE 3, an amount equal to 40% of the Fully Allocated Cost of
Performance (the "Contract Base Price") together with an Administrative Services
Fee equal to 20% of the Contract Base Price (the "Engineering/Spectrum
Management Services Contract Price").  The Company shall also be 

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responsible for reimbursement of expenses associated with the performance of 
Manager's responsibilities hereunder directly related to the Company's 
Spectrum or properly allocated thereto, including but not limited to travel 
and lodging, filing fees, legal and accounting fees, and the costs associated 
with any independent contractor retained to deal solely with the Company's 
Spectrum; provided, that all such amounts are authorized and identified in 
the Business Plan or Approved Budget.  All such amounts shall be determined 
and paid as provided in this SECTION 3.1.  

     (b)  FULLY ALLOCATED COST OF PERFORMANCE.  The "Fully Allocated Cost of
Performance" shall be calculated by taking the sum of (i) all AMI Personnel
Costs, (ii) all AMI Office Rent Expenses, (iii) all AMI Equipment Expense and
(iv) AMI Contractor Expenses.  The "AMI Personnel Costs" shall be the full costs
of each AMI employee (including professional, support and secretarial staff),
including without limitation their base salary, bonus (not to exceed 20% of base
salary), retirement and health and welfare benefits and all associated taxes and
withholdings.  The "AMI Office Rent Expenses" shall include all payments
required under the lease of the office space at 2102 Wilson Blvd., Arlington,
VA.  "AMI Equipment Expense" shall mean the cost of all equipment purchased for
use by AMI Personnel (including computer equipment), but shall not include any
allocation of general office supplies, which shall be absorbed by AMI as part of
the Administrative Services Fee.  

     (c)  REIMBURSABLE EXPENSES.  The Company will also be responsible for
paying all of the Manager's out-of-pocket expenses related to the
Engineering/Spectrum Management Services (including, without limitation, third
party copying charges) and the Manager's expenses related to the
Engineering/Spectrum Management Services performed directly for  the benefit of
the Company's business, such as postage, telephone and facsimile bills,
dedicated telephone lines, transition services, etc., all such amounts to be
authorized and identified in the Approved Budget appended to the Business Plan,
without the Company's consent.  Office supplies and general office expenses
(such as coffee machines and similar non-essential sundry items) shall not be
reimbursed but shall be considered a part of the Administrative Service Fee.

     (d)  PAYMENT TERMS.   The Engineering/Spectrum Management Contract Price
shall be estimated for a three month period and paid at the beginning of each
such three (3) month period during the term of this Agreement, with the actual
Fully Allocated Cost of Performance calculated and an appropriate adjustment
payment made for actual expenses within 20 days following the end of each such
period during the term.  Reimbursable Expenses as provided in SECTION 3.1(C)
shall be payable immediately upon submission of invoices therefor, with
appropriate supporting documentation, all in form and substance reasonably
acceptable to the Company.  Late amounts shall bear interest after the fifth day
at the rate of one half of one percent per month, compounded monthly, or such
lesser amount as may be provided under applicable law.  

     (e)  COMPANY'S RIGHT TO AUDIT.  The Company at its own expense and through
its 

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independent accountants, shall have access at reasonable times upon 
reasonable notice, to inspect all records relating to the services performed 
hereunder and all fees, charges and expenses payable by the Company.  Should 
there be found a variance of 5% or more from the Approved Budget, which 
variance shall have been reasonably conceded by Manager, then Manager shall 
pay the reasonable cost of such investigation.

     3.2  ACTING COO.  In consideration for Manager's provision of an acting
COO, the Company shall pay to Manager, for the first 6 months of the term of
this Agreement, 75% of the applicable CAI Personnel Cost for the individual
provided by Manager to the Company as acting COO.  Amounts payable under this
Section 3.2 shall be payable monthly in advance and shall not exceed the amount
for such services contained in the Approved Budget.  The parties hereto agree to
negotiate in good faith an appropriate percentage of the CAI Personnel Cost for
the acting COO for the period following the initial 6 months of the term of this
Agreement.  

     3.3  ACTING CEO SERVICES.  In consideration for Manager's provision of an
acting CEO, the Company shall pay to Manager, for the first 6 months of the term
of this Agreement, 30% of the applicable CAI Personnel Cost for the individual
provided by Manager to the Company as acting CEO.  Amounts payable under this
Section 3.3 shall be payable monthly in advance and shall not exceed the amount
for such services contained in the Approved Budget.  The parties hereto agree to
negotiate in good faith an appropriate percentage of the CAI Personnel Cost for
the acting CEO for the period following the initial 6 months of the term of this
Agreement.

                                      ARTICLE 4
                             TERM OF AGREEMENT/IP RIGHTS

     4.1  TERM.  This Agreement shall be effective from the date hereof and 
shall terminate on the fifth anniversary hereof, at which time it may be 
renewed, extended, or modified by a written agreement signed by both parties 
hereto; provided, however, that, in the event that either party hereto 
materially or repeatedly defaults in the performance of any of its duties or 
obligations hereunder and does not substantially cure such default within 
thirty (30) days after being given written notice specifying the default, or, 
with respect to those defaults which cannot reasonably be cured within thirty 
(30) days, if the defaulting party fails to proceed promptly after being 
given such notice to commence curing the default and thereafter to proceed to 
cure the same, then the party not in default may, by giving notice thereof to 
the defaulting party, terminate this Agreement as of a date specified in such 
notice of termination.

     4.2  EARLY TERMINATION OF SECTIONS 2.5, 2.6, 3.2 AND 3.3.  The Company may,
upon ten (10) business days written notice and payment in full of all
outstanding amounts hereunder, if any, terminate either or both of the Acting
CEO Services under SECTION 2.5 and the Operational Management Services under
SECTION 2.6, provided that the Company is not otherwise in default of its
obligations hereunder.  Upon such termination the Company's obligations under
SECTION 3.3 and/or SECTION 3.2, as the case may be, shall cease and the 

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balance of this Agreement shall continue in full force and effect.

     4.3  RIGHTS TO INTELLECTUAL PROPERTY.  The Company agrees that all 
inventions, discoveries, improvements, computer software, firmware, programs, 
documentation, manuals and other works or authorship (collectively 
"Intellectual Property"), whether or not copyrightable or patentable, made, 
created, developed, written or conceived by Manager during the provision of 
services under this Agreement will not be deemed work for hire.  All such 
Intellectual Property will be property of Manager.  Company hereby assigns to 
Manager all right, title and interest in and to all Intellectual Property.  
Notwithstanding anything to the contrary set forth herein, Manager hereby 
grants a royalty-free license in perpetuity to Company to use the 
Intellectual Property in the markets in which the Company has Spectrum during 
the term of this Agreement and notwithstanding the termination of this 
Agreement.

     4.4  SURVIVAL OF CERTAIN PROVISIONS.   Company agrees that notwithstanding
the termination of this Agreement pursuant to SECTION 3.1 hereto Section 4.3,
and ARTICLES 6 and 9 shall survive any such termination and remain in full force
and effect.

                                      ARTICLE 5
                           RISK OF LOSS; INSURANCE AND LAWS

     5.1  RISK.   Manager shall provide for all proper safeguards and shall
assume all risks of loss to Manager and its employees incurred in performing
Services hereunder.

     5.2  INSURANCE.   Manager shall provide the insurance coverage written with
an authorized carrier rated "B+" or better, and deliver to Company certificates
for the following insurance:

     (a)  Comprehensive General Liability, with limits of liability to be
$1,000,000 general aggregate including products and completed operations,
contractual liability and personal injury, such policy to be written on an
occurrence form;

     (b)  Comprehensive Automobile Liability, with limits of liability to be
$500,000 combined single limit, such coverage to include all owned autos, hired
and non-owned, automobile bodily injury, personal liability and automobile
property damage;

     (c)  Workers' Compensation with limits of liability to be $100,000 for each
accident, $500,000 Disease-Policy Limit, $500,000 Disease with respect to each
Employee; and

     (d)  All policies shall name CS Wireless Systems, Inc. as an additional
insured regarding any work performed pursuant to the terms hereof.

     5.3  LAWS.   Manager shall comply with applicable federal, state and local
laws and 

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regulations (i) governing health and safety of its employees assigned to 
perform Services, (ii) applicable to the performance of its Services and 
(iii) to all acts taken and omissions on behalf of the Company.

                                  ARTICLE 6
                           PERFORMANCE OF SERVICES

     6.1  CONDUCT OF PERSONNEL.   Without limiting the responsibility of 
Manager for the proper conduct of its personnel in the performance of 
services hereunder, the conduct of the personnel performing Services is to be 
guided by the representative designated by the Management Committee of 
Company and any additional special written instructions as may be agreed to 
by Manager and Company.  Company acknowledges that Manager shall recruit and 
use its best efforts to hire, either as an employee or consultant, third 
parties to provide engineering and technical services and/or assist the 
Manager and Company with respect to the Services.  Manager agrees that its 
personnel rendering Services shall cooperate with Company's employees and 
consultants and accept all assistance provided.

     6.2  SUPERVISION.   Manager is responsible for the direct management and 
supervision of its personnel through such representative approved by Company 
and such representative will, in turn, be available at all reasonable times 
to report and confer with the designated agents or representatives of Company 
with respect to Services being rendered.

     6.3  QUALIFICATIONS AND REMOVAL.   Manager agrees that services to be 
provided will be performed by qualified, careful and efficient employees in 
strict conformity with the best practices and highest applicable Standards. 
Manager further agrees that upon request of Company, it will remove from the 
performance of services at a facility of the Company any of its employees 
who, in the reasonable opinion of Company are not acting in the best 
interests of the Company and after notice to Manager and a period of two 
business days to correct the behavior, continue to act in a manner materially 
adverse to the best interests of the Company.

     6.4  REPORTS.   Manager shall supply Company promptly after such reports
become available with all internal written reports describing the progress and
results of all services performed during the term hereof.  In addition, Manager
and its personnel shall deliver to Company oral reports concerning the Services
from time to time as reasonably requested by Company.

                                      ARTICLE 7
                               CONFIDENTIAL INFORMATION

     7.1  RESTRICTION.   Each party hereto agrees not to use or disclose to
anyone other than their respective employees who need to know, during the term
of this Agreement and thereafter, any Confidential Information (as hereinafter
defined).  If requested by another party hereto, the non-requesting party shall
require its employees to execute confidentiality 

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agreements prohibiting use or disclosure of Confidential Information.  For 
purposes of this Agreement, "Confidential Information" is (a) information 
contained in any materials delivered by a party hereto pursuant to this 
Agreement, and (b) information that relates to a party's business affairs or 
that of any of its customers or affiliates.

     7.2  DELIVERY.  Upon termination of this Agreement, each party hereto 
shall deliver to the other or, at such other's election, destroy (which 
destruction shall be confirmed by the destroying company in writing), all 
Confidential Information.

     7.3  EXCLUSIVE OWNERSHIP.  Manager shall be the sole owner and shall 
have the exclusive ownership of and right to use and to license others to use 
the Intellectual Property.

                                      ARTICLE 8
                              EXCUSE FOR NONPERFORMANCE

     8.1  FORCE MAJEURE.    Each party hereto shall be excused from performance
hereunder for any period and to the extent that it is prevented from performing
any services pursuant hereto, in whole or in part, as a result of delays caused
by the other party or by an act of God, war, civil disturbance, court order,
labor dispute, third party nonperformance, or other cause beyond its reasonable
control, including without limitation failures or fluctuations in electrical
power, heat, light air conditioning or telecommunications equipment, and such
nonperformance shall not be a default hereunder or a grounds for termination
hereof.  Notwithstanding the foregoing, in the event such condition exists for a
period of greater than thirty (30) days, either party may terminate this
Agreement by giving the other party written notice of termination, which
termination shall be effective as of the date set forth in such notice.

                                      ARTICLE 9
                              COMPETITION AND EMPLOYEES

     9.1  SOLICITATION OF MANAGER'S EMPLOYEES.    Each party hereto agrees that
during the term of this Agreement and for a period of two (2) years immediately
following the termination of this Agreement, it shall not solicit employees of
any other party hereto or any affiliate thereof to leave the employ of such
party and become employees or consultant or otherwise provide services to the
soliciting party.

     9.2  HIRING COMPANY EMPLOYEES.   Manager agrees that it will assume the
financial obligations associated with the individuals specified on SCHEDULE 9.2
hereof forthwith and may, within 30 days of the execution of this Agreement,
assume their employment. 

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                                  ARTICLE 10
            INDEMNIFICATION AND DISCLAIMER OF CONSEQUENTIAL DAMAGES

     10.1 INDEMNIFICATION.  Manager agrees to indemnify, defend and hold 
harmless the Company and its affiliates and their respective directors, 
officers, agents, employees and controlling persons from and against any and 
all losses, claims, damages, liabilities and expenses (including the 
reasonable cost of investigating and defending against any claims therefor 
and reasonable counsel fees and expenses incurred in connection therewith) 
that result solely from the willful bad faith or gross negligence of the 
Manager in the performance of the Services that are the subject of this 
Agreement.  No express or implied warranty is made by Manager in respect of 
any Service or product provided hereunder including, without  limitation, any 
implied warranty or merchantability or fitness for a particular purpose.  The 
Company agrees to indemnify, defend and hold harmless the Manager and its 
affiliates and their respective directors, officers, agents, employees and 
controlling persons from and against any and all losses, claims, damages, 
liabilities and expenses (including the reasonable cost of investigating and 
defending against any claims therefor and reasonable counsel fees and expense 
incurred in connection therewith) that result solely from the willful bad 
faith or gross negligence of the Company.

     10.2 DISCLAIMER OF CONSEQUENTIAL DAMAGES.   IN NO EVENT WILL EITHER PARTY
BE LIABLE FOR PUNITIVE DAMAGES OR FOR INDIRECT OR CONSEQUENTIAL DAMAGES,
INCLUDING, WITHOUT LIMITATION, LOST PROFITS OF ANY PARTY, INCLUDING THIRD
PARTIES. FURTHER, NO CAUSE OF ACTION WHICH ACCRUED MORE THAN ONE (1) YEAR PRIOR
TO THE FILING OF A SUIT ALLEGING SUCH CAUSE OF ACTION MAY BE ASSERTED AGAINST
EITHER PARTY.
                                       
                                  ARTICLE 11
                              SECURITY AND RECORDS

     11.1 SECURITY.   Manager and the Company will each maintain strict 
security (i) with respect to any facilities granted access to by one to the 
other and (ii) regarding any materials or information delivered from one to 
the other or developed by Manager in the performance of Services, and Manager 
shall allow no person other than its employees, independent contractors and 
those of Company access to such materials, information or facilities.

     11.2 RECORDS.  Manager will maintain a daily record of Services rendered 
hereunder. Manager will keep such records throughout the term of this 
Agreement which records shall be available for inspection by the Company at 
Manager's reasonable request.  At the termination of this Agreement all such 
records shall be delivered to Company.

                                  ARTICLE 12
                                   GENERAL

     12.1 ASSIGNMENT.    This Agreement shall be binding on, and inure to the 
benefit of, the parties hereto and their respective representatives, 
successors, and permitted assigns, but 

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<PAGE>

neither this Agreement nor any of the rights, interests, or obligations 
hereunder shall be assigned or delegated by any of the parties hereto, 
whether by operation of law or otherwise, without the prior written consent 
of the other party (which consent may not be unreasonably withheld and/or 
delayed), nor is this Agreement intended to confer upon any other person 
other than the parties hereto any rights or remedies hereunder. Any 
assignment or delegation in violation of this Agreement shall be null and 
void AB INITIO.  Nothing in the foregoing shall be interpreted to limit the 
right of the Manager to retain third party independent contractors to provide 
all or any part of the services required hereunder; provided, however, that 
such persons shall be subject to the supervision of the Manager who shall 
remain liable for the performance of the duties hereunder, directly or 
through such third persons. 

     12.2 GOVERNING LAW.   This Agreement shall be governed by, and construed 
and interpreted in accordance with, the substantive laws of the State of 
Delaware without giving effect to any conflict of laws principle or rule that 
might require the application of the laws of another jurisdiction.

     12.3 AMENDMENT.   This Agreement, including the Schedules hereto, may be 
amended only by an instrument in writing executed by the parties.

     12.4 SECTION HEADINGS.   Section and Article headings are for reference 
purposes only and shall not affect the interpretation or meaning of this 
Agreement.

     12.5 NOTICES.   All notices pursuant to this Agreement shall be in 
writing, except as provided herein.  Notices in writing shall be sufficient 
if hand delivered or mailed by first class mail, postage prepaid, or sent by 
nationally recognized overnight courier or sent by confirmed facsimile 
transmission, with a copy by first class mail or courier, in each case to the 
attention of the person listed below and to the party intended as the 
recipient thereof at the address of such party set forth in the preamble, or 
at such other address or to the attention of such other person as such party 
shall have designated for such purpose in a written notice complying as to 
delivery with the terms of this Section.

          AMI or CAI:    CAI Wireless Systems, Inc.
                         18 Corporate Woods Boulevard, Third Floor
                         Albany, New York 12211
                         Attn:  Chief Financial Officer
                         Fax:   (518) 462-3045

          Company:       CS Wireless Systems, Inc.
                         1101 Summit Avenue,  Plano, TX 75074
                         Attn:    Chief Financial Officer
                         Fax:     (972)398-1110

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<PAGE>

     12.6 NO WAIVER OF PERFORMANCE. Failure by either party at any time to 
require performance by the other party or to claim a breach of any provision 
of this Agreement will not be construed as a waiver of any right accruing 
under this Agreement nor affect any subsequent breach, nor affect the 
effectiveness of this Agreement or any part hereof nor prejudice either party 
as regards any subsequent action.

     12.7 ENTIRE AGREEMENT; CONFLICTING PROVISIONS.   This Agreement, together
with the Schedules hereto, constitutes the entire agreement between Manager and
Company with respect to the subject matter hereof and no representation or
statement not contained in the main body of this Agreement or such Schedules
shall be binding upon Manager or Company as a warranty or otherwise in the event
of any conflict between the terms of the main body of this Agreement and any of
the Schedules hereto, the terms of the main body of this Agreement shall govern.

     12.8 TRADEMARKS.  Manager shall use its own name or trademarks in all
dealings.  It may not use any trademarks or trade names or rights to use same
belonging to the Company and/or its subsidiaries or affiliates (other than the
Manager) without the Company's prior written consent in each instance.  Company
shall use its own name or trademarks in all dealings.  It may not use any
trademarks or trade names or rights to use same belonging to the Manager and/or
its subsidiaries or affiliates (other than the Company) without the Manager's
prior written consent in each instance.

     12.9  NO THIRD PARTY BENEFICIARIES.  This Agreement and the rights and 
obligations hereunder do not and shall not confer any rights to any third 
parties and no third parties shall have any rights under this Agreement

     12.10  ATTORNEYS' FEES.  In the event that attorneys' fees or other
costs are incurred to secure performance of any of the obligations set forth in
this Agreement, to establish damages for the breach thereof, or to obtain any
other appropriate relief, whether by way or prosecution or defense, the
prevailing party (as determined by the judge, or other trier of fact, in its
sole discretion) shall be entitled to recover reasonable attorneys' fees and
costs incurred therein.

     12.11  COUNTERPARTS.  This Agreement may be executed in one or more 
counterparts for the convenience of the parties hereto, all of which together 
shall constitute one and the same instrument.

     12.12  SEVERABILITY.  If any provision of this Agreement is declared or 
found to be illegal, unenforceable or void, then each party will be relieved 
of its obligations arising under such provision to the extent such provision 
is declared or found to be illegal, unenforceable or void (it being the 
intent and agreement of the parties that this Agreement shall be deemed 
amended by modifying such provision to the extent necessary to make it legal 
and enforceable while preserving its intent or, if that is not possible, by 
substituting therefor another provision that is legal and enforceable and 
achieves the same objective), and each provision not so affected will be 
enforced to the full extent permitted by law.

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<PAGE>

     12.13  RELATIONSHIP OF PARTIES.  It is the express intention and 
understanding of the Manager and the Company that the relationship of the 
Manager to the Company shall be at all times that of an independent 
contractor, with the Manager having full and complete liberty to use its own 
free and uncontrolled will, judgment and discretion as to the method and 
manner of performing the obligations of the Manager hereunder.  Other than 
the Services specifically stated herein to be performed by Manager, Manager 
does not undertake by this Agreement or otherwise to perform any regulatory  
or contractual obligation of Company, or to assume any responsibility for 
Company's business or operations.  Nothing herein contained or done pursuant 
to this Agreement shall constitute the Manager or its agents or employees a 
partner or joint venturer of the Company, or a fiduciary of (i) the Company, 
(ii) any benefit plan of the Company, or (iii) any employee of the Company.

     12.14  OTHER DOCUMENTS.  Each party hereto agrees to execute any and all 
documents, and to perform such other acts, that may be necessary or expedient 
to further the purposes of this Agreement.

     IN WITNESS WHEREOF, the parties hereto have respectively caused this
Agreement to be executed by their duly authorized officers as of the day and
year first written above.



                                   CS Wireless Systems, Inc.
     
     
                                   By:       /s/ John M. Lund
                                   Name:     John M. Lund
                                   Title:    CFO

                                   CAI Wireless Systems, Inc.
     
     
                                   By:       /s/ James P. Ashman
                                   Name:     James P. Ashman
                                   Title:    EVP and CFO

                                   CAI/AMI Spectrum Management, Inc.
     
     
                                   By:       /s/ James P. Ashman
                                   Name:     James P. Ashman
                                   Title:    EVP


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