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                                                                   EXHIBIT 10.21

                              EMPLOYMENT AGREEMENT

         This Employment Agreement (this "Agreement") is entered into this date
by and between ALAMOSA PCS, LLC, a Texas Limited Liability Company, having its
principal executive office located at 4403 Brownfield Highway, Lubbock, Texas
79407 (the "Company"), and KENDALL COWAN, an individual residing at 8402
Vicksburg, Lubbock, Texas (the "Employee").

                                   WITNESSETH:

         WHEREAS, the parties are entering into this Agreement to set forth and
confirm their respective rights and obligations with respect to the Employee's
employment by the Company.

         NOW, THEREFORE, in consideration of the mutual covenants herein
contained, the parties hereto mutually agree as follows:

         1. EMPLOYMENT; TERM; DUTIES. The Company hereby employs the Employee as
Chief Financial Officer ("CFO"). The term of the Employee's employment, pursuant
to this Agreement, will commence on December 1, 1999, (the "Commencement Date")
and will continue until November 30, 2004, or the termination of this Agreement
as described in Section 6 hereof, whichever shall occur first. The Employee
hereby accepts such employment, and agrees to devote his full time and effort to
the business and affairs of the Company with such duties consistent with the
Employee's position as may be assigned to him from time to time by the Board of
Managers of the Company and/or the Chief Executive Officer ("CEO") of the
Company. The CFO shall report to the CEO of the Company. Notwithstanding the
foregoing, the Company acknowledges that the Employee has other business
interests and ownerships as well as serving on the Boards of Directors of other
companies in which the Employee is a stockholder or owner. Subject to the
provisions of Sections 8 through 11 hereof, the Company acknowledges and
consents to the continuation of these ownerships and relationships, provided
they do not interfere with the Employee's duties under this Agreement.
Notwithstanding anything to the contrary in this Agreement, nothing in this
Agreement shall be deemed to impose any obligation on the Company or any of its
subsidiaries to continue to employ the Employee, or on the Employee to remain in
the employ of the Company or any of its subsidiaries.

         2. COMPENSATION. In consideration of all services rendered by the
Employee as CFO during the term of his employment, pursuant to this Agreement,
the Company will provide the Employee with the following compensation:

                  (a) BASE SALARY. The Company will pay the Employee a base
                  salary at the annual rate of $150,000.00, payable periodically
                  but no less often than semi-monthly, in substantially equal
                  amounts, in accordance with the

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                  Company's payroll practices from time to time in effect. The
                  Company will review the Employee's base salary at least once
                  each year and may, in its discretion, increase the Employee's
                  base salary.

                  (b) BONUS. In addition to the Employee's base salary, the
                  Employee shall be eligible to receive a bonus (a "Quarterly
                  Bonus") for each calendar quarter in an amount, if any,
                  determined as follows: In each calendar quarter, beginning
                  with the quarter ending December 31, 1999, Employee's
                  Quarterly Bonus shall be equal to the sum of (1) plus (2) as
                  follows:

                                            (1) $18,750.00 multiplied by the
                           percentage set forth opposite each Expected Milestone
                           set forth in the attached EXHIBIT "A", incorporated
                           herein by reference, which is achieved for that
                           calender quarter.

                           (2) $18,750.00 multiplied by the percentage set forth
                           opposite each Exceptional Milestone set forth in
                           EXHIBIT "A" which is achieved for that calendar
                           quarter.

                  If any particular Expected Milestone or Exceptional Milestone
                  is not achieved for any calendar quarter, that percentage
                  share of the dollar amount specified in (1) or (2) above, as
                  the case may be, shall not be payable as part of the Quarterly
                  Bonus. The Expected Milestones, Exceptional Milestones and
                  percentages set forth on EXHIBIT "A" may be changed by the
                  Company at any time and from time to time, but any such change
                  shall not apply earlier than the calendar quarter following
                  the calendar quarter in which such change is made by the
                  Company and communicated to the Employee.

                  Any Quarterly Bonus owing to the Employee shall be paid within
                  forty-five (45) days following the end of the applicable
                  calendar quarter.

                  (c) UNIT OPTIONS. If, on June 30, 2000, the Company has not
                  become a wholly-owned subsidiary of Alamosa PCS Holdings,
                  Inc., a Delaware corporation ("Holdings"), then on said date
                  the Company will convert the membership interests in the
                  Company to forty-eight million five hundred thousand
                  (48,500,000) membership units, and shall grant to the Employee
                  options to purchase membership units in the Company as
                  follows:

                           (1) Option. An option (the "Option") to purchase one
                           million four hundred fifty-five thousand (1,455,000)
                           membership units in the Company at a per unit
                           purchase price equal to Fifteen Dollars ($15.00),
                           said Option, subject to Section 7 hereof, to vest and
                           be


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                           exercisable by the Employee in five (5) equal
                           installments of two hundred ninety-one thousand
                           (291,000) membership units each on November 30, 2000,
                           November 30, 2001, November 30, 2002, November 30,
                           2003, and November 30, 2004, respectively, and
                           thereafter be exercisable at any time until January
                           5, 2009, in accordance with the option agreement to
                           be entered into between the Company and the Employee
                           as of July 31, 2000, upon terms and conditions
                           substantially similar to the terms and conditions of
                           the Nonqualified Stock Option Agreement entered into
                           by the Employee pursuant to the Alamosa PCS Holdings,
                           Inc. 1999 Long-Term Incentive Plan.

The Employee will receive no additional compensation for serving the Company in
any other capacity.

         3. EMPLOYEE BENEFITS. The Employee will be entitled to participate in
all incentive, retirement, profit-sharing, life, medical, disability and other
benefit plans and programs (collectively "Benefit Plans") as are from time to
time generally available to other executives of the Company with comparable
responsibilities, subject to the provisions of those programs. Without limiting
the generality of the foregoing, the Company will provide the Employee with
basic health and medical benefits on the terms that such benefits are provided
to other executives of the Company with comparable responsibilities. The
Employee will also be entitled to holidays, sick leave and vacation in
accordance with the Company's policies as they may change from time to time, but
in no event shall the Employee be entitled to less than four (4) weeks paid
vacation per year.

         4. ADDITIONAL BENEFITS FOR EMPLOYEE. The Employee is a licensed
Certified Public Accountant. The Company acknowledges that it would be in the
best interest of the Company for the Employee to maintain such license. As
additional benefits to the Employee under this Agreement related to such
license, the Company agrees to either pay directly or reimburse the Employee
during the term of this Agreement for each of the following:

                  (a) Continuing Professional Education (CPE). The Employee is
                  required to maintain CPE classes. The Company will pay or
                  reimburse the costs of such classes sufficient for Employee to
                  maintain his license, but such payment shall be limited to the
                  cost of such classes (i.e. tuition and books) and the direct
                  costs associated with such classes, such as travel to and from
                  and housing, including hotel and meals for the Employee only.


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                  (b) Dues and Licenses. The Company will pay or reimburse the
                  Employee for all professional dues and licenses attributable
                  to the Employee's license, including but not limited to the
                  following:

                           (1)  Texas Society of CPAs;

                           (2)  American Institute of CPAs; and

                           (3)  Annual License Fees, Texas State Board of
                                Accountancy.

         5. EXPENSES.

                  (a) Reimbursement for Expenses. The Company will promptly
                  reimburse the Employee, in accordance with the Company's
                  policies and practices in effect from time to time, for all
                  expenses reasonably incurred by the Employee in performance of
                  the Employee's duties under this Agreement, including
                  reimbursement for miles driven by the Employee in furtherance
                  of the Company's business ("Business Mileage").

                           (1) Reimbursement for Business Mileage shall be at
                           the standard mileage rate allowed by the Internal
                           Revenue Service ("IRS") for the taxable year and set
                           forth in the appropriate IRS publication.

                           (2) Business mileage does not include commuting from
                           Employee's residence to the Company's headquarters.

                           (3) Employee is responsible for proper substantiation
                           and reporting of Business Mileage and/or actual
                           expenses.

                           (4) Employee acknowledges that the payment to him of
                           a monthly vehicle allowance plus the standard mileage
                           rate may result in taxable income if the business
                           portion of actual automobile expenses is less than
                           the total amount paid to employee under this
                           subsection, or if employee does not maintain the
                           records required by the Internal Revenue Code and the
                           Regulations thereunder. Employee has been advised to
                           consult a tax advisor to determine the taxability of
                           payments under this subsection, and the record
                           keeping requirements associated with the travel and
                           expenses associated with such payments.

                  (b) Expense Allowance. In addition to reimbursed expenses,
                  Employee is entitled to $600.00 per month as a vehicle
                  allowance.

         6. TERMINATION. The Employee's employment by the Company: (a) shall
terminate upon the Employee's death or disability (as defined below); (b) may be
terminated by the Company for any reason other than cause or nonperformance at
any


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time; (c) may be terminated by the Company for cause (as defined below) at any
time; (d) may be terminated by the Employee, without cause at any time upon
forty-five (45) days' prior written notice delivered by the Employee to the
Company; (e) may be terminated by the Employee for cause (as defined below) at
any time upon forty-five (45) days' prior written notice delivered by the
Employee to the Company; and (f) may be terminated by the Company for
non-performance by the Employee at any time.

                  (a) The term "disability" means the determination under the
                  Company's Long-Term Disability Plan that the Employee is
                  eligible to receive a disability benefit.

                  (b) The term "cause" in the event of termination of the
                  Employee's employment by the Company means (i) any breach of
                  Sections 8 or 10 of this Agreement by Employee which has a
                  materially adverse effect on the Company and which is not or
                  cannot be cured within thirty (30) days after notice from the
                  CEO or the Board of Managers of the Company thereof; (ii)
                  commission of any act of fraud, embezzlement or dishonesty by
                  the Employee that is materially and demonstrably injurious to
                  the Company; (iii) any act or omission by Employee which
                  constitutes a uncured default or breach of that certain Sprint
                  PCS Management Agreement dated July 17, 1998 and as it may be
                  amended from time to time or any other similar Sprint
                  Management Agreement to which the Company or any of its
                  affiliates or subsidiaries may be a party ("the Sprint
                  Agreement"); or (iv) any other intentional misconduct by the
                  Employee adversely affecting the business or affairs of the
                  Company in a material manner. The term "intentional misconduct
                  by the Employee adversely affecting the business or affairs of
                  the Company" shall mean such misconduct that is detrimental to
                  the business or the reputation of the Company as it is
                  perceived both by the general public and the
                  telecommunications industry.

                  (c) The term "cause" in the event of termination of the
                  Employee's employment by the Employee means (i) a dispute
                  between the Company and the Employee over accounting issues
                  provided, however, any such dispute shall not constitute
                  "cause" if the Company, at its own expense, elects to have a
                  nationally recognized public accounting firm resolve the
                  accounting issue dispute and such accounting firm agrees with
                  the Company's position regarding such accounting issue; (ii)
                  termination of employment by the Employee at any time more
                  than six (6) months after the date of termination by the
                  Company for any reason of the employment of David Sharbutt as
                  Chief Executive Officer of the Company ("Sharbutt's
                  Termination"), provided the Employee, within sixty (60) days
                  of the date of Sharbutt's Termination, notifies the Company in
                  writing of his intention to terminate employment under this
                  provision and specifies in such notice his date of employment
                  termination; (iii) the requirement by the Company of

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                  the relocation of the Employee from Lubbock, Texas; (iv) the
                  change in job responsibilities of the Employee resulting in
                  the demotion of the Employee from the position of CFO, which
                  demotion is caused by something other than would be cause for
                  termination of the Employee's employment by the Company for
                  cause and other than the non-performance of the Employee as
                  defined later herein; or (v) the failure of the Company to
                  complete its initial public offering (IPO) on or before
                  December 31, 2000.

                  (d) The term "non-performance by the Employee" in the event of
                  termination of the Employee's employment by the Company means
                  the determination by a super-majority (greater than 75%) of
                  the members of the Board of Managers of the Company, in their
                  sole and absolute discretion, that the Employee is not
                  performing his duties under this Agreement after the CEO or
                  the Board of Managers of the Company has delivered to the
                  Employee written notice which specifically identifies the
                  manner in which the CEO or the Board believes he is not
                  performing his duties and which is not or cannot be cured
                  within 15 days after such written notice is delivered to the
                  Employee.

         7. CONSEQUENCES OF TERMINATION.

                  (a) CONSEQUENCES OF TERMINATION ON EMPLOYEE'S DEATH OR
                  DISABILITY. If the Employee's employment is terminated prior
                  to November 30,2004, because of the Employee's death or
                  disability, (i) subject to Section 7(g) hereof, this Agreement
                  terminates immediately; (ii) Employee or his legal
                  representative or estate, as the case may be, shall be
                  eligible to exercise any options granted and vested pursuant
                  to Section 2(c) hereof at the time of such death or
                  disability, plus, if such death or disability does not occur
                  on November 30 of a given year, a fractional portion of those
                  options which would have vested and become exercisable
                  pursuant to Section 2(c) hereof on the November 30 immediately
                  following such death or disability based on a fraction whose
                  numerator is the number of months (including the month in
                  which the date of death or disability occurs) since the
                  previous November 30 and whose denominator is twelve (12), in
                  accordance with the provisions of Section 2(c) hereof and the
                  option agreement referred to therein, and any other options
                  granted to the Employee shall be forfeited; (iii) the Company
                  will pay the Employee, or his legal representative or estate,
                  as the case may be, in full satisfaction of all of its
                  compensation (base salary and bonus) obligations under this
                  Agreement, an amount equal to the sum of any base salary due
                  to the Employee through the last day of employment, plus any
                  accrued bonus to which the Employee may have been entitled on
                  the last day of employment, but had not yet been received; and
                  (iv) the Employee's benefits and rights under any Benefit Plan
                  shall be paid, retained or


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                  forfeited in accordance with the terms of such plan; provided,
                  however, that Employer shall have no obligation to make any
                  payments toward these benefits for Employee from and after
                  termination.

                  (b) CONSEQUENCES OF TERMINATION BY THE COMPANY FOR ANY REASON
                  OTHER THAN FOR CAUSE OR FOR NON-PERFORMANCE OF EMPLOYEE.

                           (1) If the Employee's employment is terminated by the
                           Company prior to November 30, 2004, for any reason
                           other than for cause or non-performance of Employee,
                           (i) subject to Section 7(g) hereof, this Agreement
                           terminates immediately; (ii) Employee or his legal
                           representative or estate, as the case may be, shall
                           be eligible to exercise any options granted but not
                           exercised pursuant to Section 2(c) hereof, which
                           options shall be deemed vested as of the date of the
                           Employee's termination of employment regardless of
                           whether or not they are in fact otherwise vested
                           pursuant to Section 2(c) hereof on said date, in
                           accordance with the provisions of Section 2(c) hereof
                           and the option agreement referred to therein; (iii)
                           the Company will pay the Employee, in full
                           satisfaction of all of its compensation (base salary
                           and bonus) obligations under this Agreement, an
                           amount equal to the sum of any base salary due to the
                           Employee through the last day of employment, plus any
                           accrued bonus to which the Employee may have been
                           entitled on the last day of employment, but had not
                           yet been received; (iv) the Company will pay the
                           Employee, within sixty (60) days of such termination,
                           a lump sum severance payment equal to one (1) year's
                           base salary as in effect at the date of employment
                           termination; and (v) the Employee's benefits and
                           rights under any Benefit Plan, other than any basic
                           health and medical benefit plan, shall be paid,
                           retained or forfeited in accordance with the terms of
                           such plan; provided, however, that Employer shall
                           have no obligation to make any payments toward these
                           benefits for Employee from and after termination.

                           (2) Any payment pursuant to clause (b)(1)(iv) above
                           (the "Termination Payment"):

                                    a. will be subject to offset for any
                                    advances, amounts receivable, and loans,
                                    including accrued interest, outstanding on
                                    the date of the employment termination; and

                                    b. will not be subject to offset on account
                                    of any remuneration paid or payable to the
                                    Employee for any subsequent employment the
                                    Employee may obtain, whether


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                                    during or after the period during which the
                                    Termination Payment is made, and the
                                    Employee shall have no obligation whatever
                                    to seek any subsequent employment.

                  (c) CONSEQUENCES OF TERMINATION FOR CAUSE BY THE COMPANY. If
                  the Employee's employment is terminated by the Company prior
                  to November 30, 2004, for cause, (i) subject to Section 7(g)
                  hereof, this Agreement terminates immediately; (ii) Employee
                  shall not be eligible to exercise and shall forfeit any
                  options granted (whether or not vested) pursuant to Section
                  2(c) hereof at the time of such employment termination that
                  have not already been exercised by the Employee at the time of
                  such employment termination; (iii) the Company will pay the
                  Employee, in full satisfaction of all of its compensation
                  (base salary and bonus) obligations under this Agreement, an
                  amount equal to the sum of any base salary due to the Employee
                  through the last day of employment, plus any accrued bonus to
                  which the Employee may have been entitled on the last day of
                  employment, but had not yet been received; and(iv) the
                  Employee's benefits and rights under any Benefit Plan shall be
                  paid, retained or forfeited in accordance with the terms of
                  such plan; provided, however, that Employer shall have no
                  obligation to make any payments toward these benefits for
                  Employee from and after termination.

                  (d) CONSEQUENCES OF TERMINATION BY THE EMPLOYEE FOR ANY REASON
                  OTHER THAN FOR CAUSE OR EMPLOYEE'S DEATH OR DISABILITY. If,
                  upon forty-five (45) days' prior written notice to the Company
                  by the Employee, the Employee's employment is terminated by
                  the Employee prior to November 30, 2004, for any reason other
                  than for cause or Employee's death or disability, (i) subject
                  to Section 7(g) hereof, this Agreement terminates immediately;
                  (ii) Employee or his legal representative or estate, as the
                  case may be, shall be eligible to exercise any options granted
                  and vested, but not exercised pursuant to Section 2(c) hereof
                  at the time of such employment termination, in accordance with
                  the provisions of Section 2(c) hereof and the option agreement
                  referred to therein, and any other options granted to the
                  Employee shall be forfeited; (iii) the Company will pay the
                  Employee, in full satisfaction of all of its compensation
                  (base salary and bonus) obligations under this Agreement, an
                  amount equal to the sum of any base salary due to the Employee
                  through the last day of employment, plus any accrued bonus to
                  which the Employee may have been entitled on the last day of
                  employment, but had not yet been received; and (iv) the
                  Employee's benefits and rights under any Benefit Plan, other
                  than any basic health and medical benefit plan, shall be
                  retained or forfeited in accordance with the terms of such
                  plan; provided, however, that Employer shall have no


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                  obligation to make any payments toward these benefits for
                  Employee from and after termination.

                  (e) CONSEQUENCES OF TERMINATION BY THE EMPLOYEE FOR CAUSE.

                           (1) If, upon forty-five (45) days' prior written
                           notice to the Company by the Employee, the Employee's
                           employment is terminated by the Employee prior to
                           November 30, 2004, for cause (i) subject to Section
                           7(g) hereof, this Agreement terminates immediately;
                           (ii) Employee or his legal representative or estate,
                           as the case may be, shall be eligible to exercise any
                           options granted and vested pursuant to Section 2(c)
                           hereof at the time of such employment termination,
                           plus, if such employment termination does not occur
                           on November 30 of a given year, those options which
                           would have vested and become exercisable pursuant to
                           Section 2(c) hereof on the November 30 immediately
                           following such employment termination, in accordance
                           with the provisions of Section 2(c) hereof and the
                           option agreement referred to therein, and any other
                           options granted to the Employee shall be forfeited;
                           (iii) the Company will pay the Employee, in full
                           satisfaction of all of its compensation (base salary
                           and bonus) obligations under this Agreement, an
                           amount equal to the sum of any base salary due to the
                           Employee through the last day of employment, plus any
                           accrued bonus to which the Employee may have been
                           entitled on the last day of employment, but had not
                           yet been received; (iv) the Company will pay the
                           Employee, within sixty (60) days of such termination,
                           a lump sum severance payment equal to one (1) year's
                           base salary as in effect at the date of employment
                           termination or the unpaid balance of the annual base
                           salary which would have been payable to Employee
                           through November 30, 2004, whichever amount shall be
                           less; and (v) the Employee's benefits and rights
                           under any Benefit Plan, other than any basic health
                           and medical benefit plan, shall be paid, retained or
                           forfeited in accordance with the terms of such plan;
                           provided, however, that Employer shall have no
                           obligation to make any payments toward these benefits
                           for Employee from and after termination.

                           (2) Any payment pursuant to clause (e)(1)(iv) above
                           (the "Termination Payment"):

                                    a. will be subject to offset for any
                                    advances, amounts receivable, and loans,
                                    including accrued interest, outstanding on
                                    the date of the employment termination; and


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                                    b. will not be subject to offset on account
                                    of any remuneration paid or payable to the
                                    Employee for any subsequent employment the
                                    Employee may obtain, whether during or after
                                    the period during which the Termination
                                    Payment is made, and the Employee shall have
                                    no obligation whatever to seek any
                                    subsequent employment.

                  (f) CONSEQUENCES OF TERMINATION BY THE COMPANY FOR
                  NON-PERFORMANCE BY THE EMPLOYEE. If the Employee's employment
                  is terminated by the Company prior to November 30, 2004, for
                  non-performance by the Employee (i) subject to Section 7(g)
                  hereof, this Agreement terminates immediately; (ii) Employee
                  or his legal representative or estate, as the case may be,
                  shall be eligible to exercise any options granted and vested
                  but not exercised pursuant to Section 2(c) hereof at the time
                  of such employment termination, in accordance with the
                  provisions of Section 2(c) hereof and the option agreement
                  referred to therein, and any other options granted to the
                  Employee shall be forfeited; (iii) the Company will pay the
                  Employee, in full satisfaction of all of its compensation
                  (base salary and bonus) obligations under this Agreement, an
                  amount equal to the sum of any base salary due to the Employee
                  through the last day of employment, plus any accrued bonus to
                  which the Employee may have been entitled on the last day of
                  employment, but had not yet been received; and (iv) the
                  Employee's benefits and rights under any Benefit Plan, other
                  than any basic health and medical benefit plan, shall be paid,
                  retained or forfeited in accordance with the terms of such
                  plan; provided, however, that Employer shall have no
                  obligation to make any payments toward these benefits for
                  Employee from and after termination.

                  (g) PRESERVATION OF CERTAIN PROVISIONS. Notwithstanding any
                  provisions of this Agreement to the contrary, the provisions
                  of Sections 8 through 13 hereof shall survive the expiration
                  or termination of this Agreement as necessary to give full
                  effect to all of the provisions of this Agreement.

         8. NON-COMPETITION BY EMPLOYEE. During the term of this Agreement, the
Employee shall not, directly or indirectly, either as an Employee, Employer,
Consultant, Agent, Principal, Partner, Corporate Officer, Director, Shareholder,
Member, Investor or in any other individual or representative capacity, engage
or participate in any business that is in competition in any manner whatever
with the business of the Company. For these purposes, the business of the
Company is establishing and providing mobile wireless communications services
(the "Business"), including all aspects of the Business within the Service Area
as that term is defined in the Schedule of Definitions referred to in and
incorporated by reference into the Sprint Agreement. Furthermore,


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upon the expiration of this Agreement or the termination of this Agreement prior
to November 30, 2004, for any reason, the Employee expressly agrees not to
engage or participate, directly or indirectly, either as an Employee, Employer,
Consultant, Agent, Principal, Partner, Stockholder, Corporate Officer, Director,
Shareholder, Member, Investor or in any other individual or representative
capacity, for a period of two (2) years in any business that is in competition
with the Business and that is located within and/or doing business within the
Service Area as defined above as in existence during the term of the Employee's
employment with the Company. The parties agree that the Company has a legitimate
interest in protecting the Business and goodwill of the Company that has
developed in the areas of the Company's Business and in the geographical areas
of this Covenant Not To Compete as a result of the operations of the Company.
The parties agree that the Company is entitled to protection of its interests in
these areas. The parties further agree that the limitations as to time,
geographical area, and scope of activity to be restrained do not impose a
greater restraint upon Employee than is necessary to protect the goodwill or
other business interest of the Company. The parties further agree that in the
event of a violation of this Covenant Not To Compete, that the Company shall be
entitled to the recovery of damages from Employee and/or an injunction against
Employee for the breach or violation or continued breach or violation of this
Covenant. The Employee agrees that if a court of competent jurisdiction
determines that the length of time or any other restriction, or portion thereof,
set forth in this Section 8 is overly restrictive and unenforceable, the court
may reduce or modify such restrictions to those which it deems reasonable and
enforceable under the circumstances, and as so reduced or modified, the parties
hereto agree that the restrictions of this Section 8 shall remain in full force
and effect. The Employee further agrees that if a court of competent
jurisdiction determines that any provision of this Section 8 is invalid or
against public policy, the remaining provisions of this Section 8 and the
remainder of this Agreement shall not be affected thereby, and shall remain in
full force and effect.

         9. EXCEPTIONS TO NON-COMPETITION COVENANTS. Notwithstanding anything
herein to the contrary or apparently to the contrary, the following shall not be
a violation or breach of the non-competition covenants contained in this
Agreement. Employee may invest in the securities of any enterprise (but without
otherwise participating in the activities of such enterprise) if (a) such
securities are listed on any national or regional securities exchange or have
been registered under Section 12(g) of the Securities Exchange Act of 1934 and
(b) the Employee does not beneficially own (as defined in Rule 13d-3 promulgated
under the Securities Exchange Act of 1934) in excess of 5% of the outstanding
capital stock of such enterprise. Employee's investment in any company or entity
in which Employer is an owner or stockholder at the time of entering into this
Agreement shall also be an exception to the non-competition covenants. The names
of these companies or entities are shown on the attached Exhibit B, which is
incorporated herein by this reference as if copied at length. Notwithstanding
the foregoing, the Employee's relationship with other entities or business
interests of


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Employee shall in no way interfere with or detract from the duties of the
Employee to the Company as called for in this Agreement.

         10. CONFIDENTIAL INFORMATION. The Employee recognizes and acknowledges
that he will have access to certain information of members of the Company Group
(as defined below) and that such information is confidential and constitutes
valuable, special and unique property of such members of the Company Group. The
parties agree that the Company has a legitimate interest in protecting the
Confidential Information, as defined below. The parties agree that the Company
is entitled to protection of its interests in the Confidential Information. The
Employee shall not at any time, either during or subsequent to the term of this
Agreement, disclose to others, use, copy or permit to be copied, except in
pursuance of his duties on behalf of the Company, it successors, assigns or
nominees, any Confidential Information of any member of the Company Group
(regardless of whether developed by the Employee) without the prior written
consent of the Company. Employee acknowledges that the use or disclosure of the
Confidential Information to anyone or any third party could cause monetary loss
and damages to the Company. The parties further agree that in the event of a
violation of this covenant against non-use and non-disclosure of Confidential
Information, that the Company shall be entitled to a recovery of damages from
Employee and/or an injunction against Employee for the breach or violation or
continued breach or violation of this covenant.

         As used herein, "Company Group" means the Company, and any entity that
directly or indirectly controls, is controlled by, or is under common control
with, the Company, and for purposes of this definition "control" means the
possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of such entity, whether through the
ownership of voting securities, by contract or otherwise.

         The term "Confidential Information" with respect to any person means
any secret or confidential information or know-how and shall include, but shall
not be limited to, the plans, financial and operating information, customers,
supplier arrangements, contracts, costs, prices, uses, and applications of
products and services, results of investigations, studies or experiments owned
or used by such person, and all apparatus, products, processes, compositions,
samples, formulas, computer programs, computer hardware designs, computer
firmware designs, and servicing, marketing or manufacturing methods and
techniques at any time used, developed, investigated, made or sold by such
person, before or during the term of this Agreement, that are not readily
available to the public or that are maintained as confidential by such person.
The Employee shall maintain in confidence any Confidential Information of third
parties received as a result of his employment with the Company in accordance
with the Company's obligations to such third parties and the policies
established by the Company.


Employment Agreement       PAGE 12 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   13

         11. DELIVERY OF DOCUMENTS UPON TERMINATION. The Employee shall deliver
to the Company or its designee at the termination of his employment all
correspondence, memoranda, notes, records, drawings, sketches, plans, customer
lists, product compositions, and other documents and all copies thereof, made,
composed or received by the Employee, solely or jointly with others, that are in
the Employee's possession, custody, or control at termination and that are
related in any manner to the past, present, or anticipated business or any
member of the Company Group. In this regard, the Employee hereby grants and
conveys to the Company all right, title and interest in and to, including
without limitation, the right to possess, print, copy, and sell or otherwise
dispose of, any reports, records, papers, summaries, photographs, drawings or
other documents, and writings, and copies, abstracts or summaries thereof, that
may be prepared by the Employee or under his direction or that may come into his
possession in any way during the term of his employment with the Company that
relate in any manner to the past, present or anticipated business of any member
of the Company Group.

         12. DISPUTES. The Company and Employee agree to the following in regard
to any disputes between them arising under any of the provisions of this
Agreement other than the provisions of Sections 8 through 11 hereof. Nothing in
this Section 12 applies to or governs disputes arising under Sections 8 through
11 of this Agreement.

                  (a) MEDIATION. The Company and Employee agree to mediate any
                  dispute arising under the applicable provisions of this
                  Agreement. In the event of any such dispute, the parties,
                  within thirty (30) days of a written request for mediation,
                  shall attend, in good faith, a mediation in order to make a
                  good faith reasonable effort to resolve such dispute arising
                  under this Agreement. The parties shall attempt, in good
                  faith, to agree to a mediator. If unable to so agree, the
                  parties, in that event, will move to arbitration as provided
                  in this Agreement and there will be no mediation. If this good
                  faith mediation effort fails to resolve any dispute arising
                  under this Agreement, the Company and Employee agree to
                  arbitrate any dispute arising under this Agreement. This
                  arbitration shall occur only after the mediation process
                  described herein.

                  (b) ARBITRATION. The Company and Employee agree, as concluded
                  by the parties to this Agreement on the advice of their
                  counsel, and as evidenced by the signatures of the parties and
                  of their respective attorneys, that all questions as to rights
                  and obligations arising under the terms of this Agreement are
                  subject to arbitration and such arbitration shall be governed
                  by the provisions of the Texas General Arbitration Act (Texas
                  Civil Practice and Remedies Code Section 171.001 et seq as it
                  may be amended from time to time).


Employment Agreement       PAGE 13 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   14

                  (c) DEMAND FOR ARBITRATION. If a dispute should arise under
                  this Agreement, either party may within thirty (30) days make
                  a demand for arbitration by filing a demand in writing with
                  the other.

                  (d) APPOINTMENT OF ARBITRATORS. The parties to this Agreement
                  may agree on one arbitrator, but in the event that they cannot
                  so agree, there shall be three arbitrators, one named in
                  writing by each of the parties within thirty (30) days after
                  demand for arbitration is made, and a third to be chosen by
                  the two so named. The arbitrators among themselves shall
                  appoint a presiding arbitrator. Should either party fail to
                  timely join in the appointment of the arbitrators, the
                  arbitrators shall be appointed in accordance with the
                  provisions of Texas Civil Practice and Remedies Code Section
                  171.041.

                  (e) HEARING. All arbitration hearings conducted under the
                  terms of this Agreement, and all judicial proceedings to
                  enforce any of the provisions of this Agreement, shall take
                  place in Lubbock County, Texas. The hearing before the
                  arbitrators of the matter to be arbitrated shall be at the
                  time and place within that County selected by the arbitrators
                  or if deemed by the arbitrators to be more convenient for the
                  parties or more economically feasible, may be conducted in any
                  city within the Service Area as referred to in Section 7
                  hereof or within the State of Texas.

                  (f) ARBITRATION AWARD. If there is only one arbitrator, his or
                  her decision shall be binding and conclusive. The submission
                  of a dispute to the arbitrators and the rendering of their
                  decision shall be a condition precedent to any right of legal
                  action on the dispute. A judgment confirming the award of the
                  arbitrators may be rendered by any court having jurisdiction;
                  or the court may vacate, modify, or correct the award in
                  accordance with the provisions of the Texas General
                  Arbitration Act (Texas Civil Practice and Remedies Code
                  Section 171.087 et seq as it may be amended from time to
                  time).

                  (g) COSTS OF ARBITRATION. The costs and expenses of
                  arbitration, including the fees of the arbitrators but
                  excluding any attorneys' fees, shall be advanced by the
                  Company, but will ultimately be borne by the losing party or
                  in such proportions as the arbitrators shall determine.

                  (h) CONDUCT OF ARBITRATION. Any arbitration brought under the
                  terms of this Agreement shall be conducted in the following
                  manner:

                           (1) Time Limitations. The parties agree that the
                           following time limitations shall govern the
                           arbitration proceedings conducted under the terms of
                           this Agreement:


Employment Agreement       PAGE 14 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   15

                                    (a) Any demand for arbitration must be filed
                                    within thirty (30) days of the date the
                                    mediation is deemed unsuccessful, or thirty
                                    (30) days after the date of the written
                                    request for mediation, whichever is later.

                                    (b) Each party must select an arbitrator
                                    within thirty (30) days of receipt of notice
                                    that an arbitration proceeding has
                                    commenced. In the event that no such
                                    selection is made, the arbitrator selected
                                    by the other party may conduct the
                                    arbitration proceeding without selecting any
                                    other arbitrator.

                                    (c) The hearing must be held within sixty
                                    (60) days of the date on which the third
                                    arbitrator is selected.

                                    (d) Hearing briefs must be submitted no
                                    later than ten (10) days after the hearing.

                                    (e) The arbitration award must be made
                                    within thirty (30) days of the receipt of
                                    hearing briefs.

                           (2) Discovery in Arbitration Proceedings. The parties
                           agree that discovery may be conducted in the course
                           of the arbitration proceeding in accordance with the
                           following provisions:

                                    (a) Each party may notice no more than three
                                    (3) depositions in total, including both
                                    witnesses adherent to the adverse party and
                                    third-party witnesses.

                                    (b) Each party may serve no more than
                                    twenty-five (25) requests for admission on
                                    the other party. No requests may be served
                                    within ten (10) days of the date of hearing,
                                    unless the parties otherwise stipulate. All
                                    requests for admission shall be responded to
                                    within ten (10) days of service of the
                                    requests, unless the parties otherwise
                                    stipulate.

                                    (c) Each party may serve no more than fifty
                                    (50) interrogatories on the other party. No
                                    interrogatory shall contain subparts, or
                                    concern more than one topic or subject of
                                    inquiry. Interrogatories may not be phrased
                                    so as to circumvent the effect of this
                                    clause. No interrogatories may be served
                                    within ten (10) days of the date of hearing,
                                    unless the parties otherwise stipulate. All
                                    interrogatories shall be


Employment Agreement       PAGE 15 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   16

                                    responded to within ten (10) days of service
                                    of the interrogatories, unless the parties
                                    otherwise stipulate.

                                    (d) Each party may serve no more than ten
                                    (10) requests for production of documents on
                                    the other party. No request for production
                                    of documents shall contain subparts, or seek
                                    more than one type of document. Requests for
                                    production of documents may not be phrased
                                    so as to circumvent the effect of this
                                    clause. Unless the parties otherwise
                                    stipulate, requests for production of
                                    documents may not be served within ten (10)
                                    day of the date of hearing, and all requests
                                    for production of documents shall be
                                    responded to within ten (10) days of service
                                    of the requests.

                                    (e) If any party contends that the other
                                    party has served discovery requests in a
                                    manner not permitted by this Section, or
                                    that the other party's response to a
                                    discovery request is unsatisfactory, the
                                    party may request the presiding arbitrator
                                    to resolve such discovery disputes. The
                                    presiding arbitrator shall prescribe the
                                    procedure by which such disputes are
                                    resolved. Any discovery dispute may be
                                    handled by telephone conference among the
                                    parties and the presiding arbitrator.

         13. SUCCESSORS; BINDING AGREEMENT; ASSIGNMENT. The Company shall
require any successor (whether direct or indirect, by purchase, merger,
consolidation or otherwise) to all or substantially all of the business or
assets of the Company to expressly assume and agree in writing to perform this
Agreement in the same manner and to the same extent that the Company would be
required to perform it if no such succession had taken place, provided that the
Employee must be given the position as the Chief Financial Officer ("CFO") with
the same authority, powers and responsibilities set forth in Section 1 hereof
with respect to the subsidiary or subdivision which operates the business of the
Company as it exists on the date of such business combination. Failure of the
Company to obtain such express assumption and agreement at or prior to the
effectiveness of any such succession shall be a breach of this Agreement and
shall entitle the Employee to compensation and benefits from the Company in the
same amount and on the same terms to which the Employee would be entitled
hereunder if the Company terminated the Employee's employment without Cause,
except that all options will be immediately vested. For purposes of implementing
the foregoing, the date on which any such succession becomes effective shall be
deemed the date of termination. As used in this Agreement, "Company" shall mean
the Company as hereinbefore defined and any successor to its business or assets
as aforesaid which assumes and agrees to perform this Agreement by operation of
law, or otherwise. The Company may not assign this Agreement, (i) except in
connection with, and to the

Employment Agreement       PAGE 16 OF 21
Alamosa PCS LLC and Kendall Cowan

<PAGE>   17


acquiror of, all or substantially all of the business or assets of the Company,
provided such acquiror expressly assumes and agrees in writing to perform this
Agreement as provided in this Section, and (ii) except in connection with the
Company becoming a wholly-owned subsidiary of Holdings, in which event the
Company may assign this Agreement and all of the Company's rights and
obligations hereunder to Holdings. The Employee may not assign his rights or
delegate his duties or obligations under this Agreement.

         14. NOTICE. Any notices or other communications required or permitted
to be given hereunder shall be in writing and shall be deemed to have been duly
made or given when hand delivered, one (1) business day after being transmitted
by telecopier (confirmed by mail) or sent by overnight courier against receipt,
or five (5) days after being mailed by registered or certified mail, postage
prepaid, return receipt requested, to the party to whom such communication is
given at the address set forth below, which address may be changed by notice
given in accordance with this Section:

         If to the Company:               Alamosa PCS LLC
                                          4403 Brownfield Highway
                                          Lubbock, Texas  79407
                                          Attn:  David E. Sharbutt, Chairman

         With Copy to:                    Jack McCutchin, Jr.
                                          Crenshaw, Dupree & Milam, L.L.P.
                                          P. O. Box 1499
                                          Lubbock, Texas 79408-1499

         If to the Employee:              Kendall Cowan
                                          8402 Vicksburg
                                          Lubbock, Texas  79424

         With Copy to:
                                          --------------------------------------
                                          --------------------------------------
                                          --------------------------------------

          15. MISCELLANEOUS.

              (a) SEVERABILITY. If any provision of this Agreement shall be
              declared to be invalid or unenforceable, in whole or in part, such
              invalidity or unenforceability shall not affect the remaining
              provisions hereof which shall remain in full force and effect.

              (b) NO ORAL MODIFICATION, WAIVER OR DISCHARGE. No provisions of
              this Agreement may be modified, waived or discharged orally, but
              only by a waiver, modification or discharge in writing signed by
              the Employee and


Employment Agreement       PAGE 17 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   18

              such officer as may be designated by the Board of Managers of the
              Company to execute such a waiver, modification or discharge. No
              waiver by either party hereto at any time of any breach by the
              other party hereto of, or failure to be in compliance with, any
              condition or provision of this Agreement to be performed by such
              other party shall be deemed a waiver of similar or dissimilar
              provisions or conditions at the time or at any prior or subsequent
              time. No agreements or representations, oral or otherwise, express
              or implied, with respect to the subject matter hereof have been
              made by either party which are not expressly set forth in this
              Agreement or in the documents attached as Exhibits to this
              Agreement.

              (c) INVALID PROVISIONS. Should any portion of this Agreement be
              adjudged or held to be invalid, unenforceable or void, such
              holding shall not have the effect of invalidating or voiding the
              remainder of this Agreement and the parties hereby agree that the
              portion so held invalid, unenforceable or void shall, if possible,
              be deemed amended or reduced in scope, or otherwise be stricken
              from this Agreement to the extent required for the purposes of
              validity and enforcement thereof.

              (d) ENTIRE AGREEMENT. This Agreement and the Exhibits attached
              hereto represent the entire agreement of the parties and shall
              supersede any and all previous contracts, arrangements or
              understandings, express or implied, between the Employee and the
              Company with respect to the subject matter hereof.

              (e) SECTION HEADINGS FOR CONVENIENCE ONLY. The section headings
              herein are for the purpose of convenience only and are not
              intended to define or limit the contents of any section.

              (f) EXECUTION IN COUNTERPARTS. The parties may sign this Agreement
              in counterparts, all of which shall be considered one and the same
              instrument.

              (g) GOVERNING LAW AND PERFORMANCE. This Agreement shall be
              governed by the laws of the State of Texas and shall be deemed to
              be executed in and performance called for in Lubbock, Lubbock
              County, Texas, or at the Company's sole option, by the laws of the
              state or states where this Agreement may be at issue in any
              litigation involving the Company.


Employment Agreement       PAGE 18 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   19

         DATED this 18th day of January, 2000, to be effective December 1, 1999.

                                     COMPANY

                                     ALAMOSA PCS LLC


                                     By     /s/ DAVID SHARBUTT
                                            -------------------------

                                     Name:  David Sharbutt
                                            -------------------------

                                     Title: Chief Executive Officer
                                            -------------------------


                                     EMPLOYEE


                                     /s/ KENDALL W. COWAN
                                     --------------------------------
                                     KENDALL W. COWAN


Employment Agreement       PAGE 19 OF 21
Alamosa PCS LLC and Kendall Cowan


<PAGE>   20

Approved as to the mediation and arbitration provisions in Paragraph 12 above.



                                     CRENSHAW, DUPREE & MILAM, L.L.P.


                                     By   /s/ JACK MCCUTCHIN, JR.
                                          --------------------------------------
                                          JACK McCUTCHIN, JR.
                                          Attorneys for Alamosa PCS LLC

                                          [SIGNATURE TO COME]
                                          --------------------------------------
                                          Attorney for Employee



Attachment:  Exhibit "A" - The Minimum, Expected and Exceptional Milestones for
             the Third Quarter and Fourth Quarter of 1999 as adopted by the
             Board of Managers of the Company

             Exhibit "B" - List of Companies or Entities Excepted from Covenants




Employment Agreement       PAGE 20 OF 21
Alamosa PCS LLC and Kendall Cowan