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                                                                   Exhibit 10.13

                              EMPLOYMENT AGREEMENT

     Agreement made this 17th day of September, 1999 between ALLIANCE MEDICAL
CORPORATION ("Employer") and DAVID A. AMRHEIN ("Employee"). The parties hereto,
intending to be legally bound hereto, agree upon the following terms of
employment of Employee by Employer.

     1.   TERM. Employment shall commence at a date to be mutually agreed upon
and shall terminate as provided in paragraph 5.

     2.   DUTIES. Employee shall perform such duties for Employer and its
affiliates as may be requested of Employee by Employer.

     3.   PERFORMANCE BY EMPLOYEE. Except as may be otherwise directed or
approved by Employer from time to time, during the period of employment under
this Agreement, Employee shall devote his full time and efforts to the business
and affairs of Employer and shall perform his duties competently and
efficiently. Employee agrees that during the period of his employment under
this Agreement he will not undertake any outside business affiliations without
the prior written approval of Employer.

     Employee may engage in such personal investment activities during the term
of this Agreement as Employee deems appropriate and consistent with Employee's
position hereunder so long as such activities do not materially interfere with
the performance of Employee's duties under this Agreement and are not in
contravention of this Agreement.

     4.   COMPENSATION. For all services to be performed by Employee during the
term of employment under this Agreement (including, without limitation,
services as an officer, director, employee, member of any committee of Employer
or of any division or subsidiary of Employer, or otherwise), Employee shall:

          (a)  Receive an annual salary at the rate of One Hundred and Ten
Thousand Dollars ($110,000) per year for the first year of such term. Salary
payments shall be made in accordance with Employer's customary practice, but not
less than bi-weekly. Employee's salary shall thereafter be subject to annual
review and adjustment by Employer, and/or by Employee's direct supervisor;

          (b)  Be eligible to earn an annual bonus of an amount not to exceed
35% of the then current annual salary. The annual bonus plan shall be reviewed
with Employee at the beginning of each fiscal year.

          (c)  In addition to any cash compensation payable hereunder, be
entitled to participate in the various fringe benefits generally made available
to employees of Employer.

          (d)  Be entitled to three (3) weeks paid vacation during each full
year that this Agreement is in force. Such vacation shall not be cumulative.
The time or times during which vacation is taken shall first be approved by
Employer.

          (e)  Be re-imbursed by Employer for any reasonable expenses incurred
in conjunction with his employment. Employee shall present to Employer an
itemized written account


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within thirty (30) days after they have been incurred. Employee shall not be
re-imbursed for expenses in substantial amounts unless they have been approved
in advance by Employer.

     5.   TERMINATION.  This Agreement shall be terminated upon the happening
of any of the following events:

          (a)  Death. The Employee's death;

          (b)  Disability. In the event Employee becomes physically or mentally
disabled so as to become unable, for a period of more than Ninety (90)
consecutive calendar days or for more than Ninety (90) calendar days in the
aggregate during any twelve-month period, to perform his duties hereunder on a
full-time basis, Employer may at its option terminate Employee's employment
hereunder upon written notice;

          (c)  Cause. Employer may terminate Employee's employment hereunder
for Cause. "Cause" shall include but not be limited to:

               (i)   dishonesty in connection with the duties to be performed by
Employee;

               (ii)  continuing inattention to or neglect of the duties to be
performed by Employee, which inattention or neglect is not the result of
illness or accident;

               (iii) willful disloyalty to Employer or any of its affiliates; or

               (iv)  violation of any of the provisions of Paragraphs 6 and 7
hereunder.

          (d)  Without Cause. Employer, at its option, may terminate Employee's
employment hereunder for any reason and without cause upon ninety (90) days
written notice to Employee.

     6.   DISCLOSURE OF INFORMATION.  Employee shall not, during or any time
after termination of employment hereunder (whether or not for cause), without
authorization of Employer, disclose or make use of for himself or for any
person or corporation or other entity, any files or trade secrets or other
confidential information concerning the business, clients, methods, operations,
financing or services of Employer or its affiliates. Trade secrets and
confidential information shall mean information disclosed to Employee or known
by him as a consequence of his employment by Employer, whether or not pursuant
to this Agreement, and not generally known to or used by competitors in
Employer's business.

     7.   COVENANT NOT TO COMPETE.

          (A)  Restrictive Covenant. For a period of two (2) years after
termination of Employee's employment, whether or not for cause, Employee shall
not, within the Restricted Area as hereinafter defined, directly or indirectly
own, operate, control, be employed by, participate in, or be connected in any
way with the ownership, management, operation or control of any business which
is substantially similar to the business of Employer or any affiliate of
Employer to which Employee has provided services. FOR PURPOSES OF THIS SECTION,
THE "RESTRICTED AREA" MEANS THE UNITED STATES OF AMERICA.

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          (B)  Solicitation of Customers or Employees. In furtherance of the
foregoing, and not in limitation thereof, for a period of two (2) years after
termination of employment (whether or not for cause), Employee shall not, within
the product market and within the Restricted Area set forth in subparagraph (A)
above, directly or indirectly solicit or service in any way, on behalf of
himself or on behalf of or in conjunction with others, any client or customer,
or prospective client or customer, which has been solicited or serviced by
Employer or any affiliate of Employer within one (1) year prior to the
termination of his employment.

               So long as Employee is employed by Employer and for a period of
two (2) years after termination of employment, Employee shall not solicit any
employee of Employer or any of its affiliates to become employed by or otherwise
associated with Employee in any other business.

          (C)  Competitive Activities. Employee shall be deemed to be competing
with Employer or soliciting a customer, prospective customer or employee of
Employer if, without the knowledge and written consent of the Board of Directors
of Employer, Employee is engaged in any such activity directly or indirectly,
whether for his own account or as a principal, agent, proprietor, officer,
director, employee, consultant or in any other capacity for any other person,
corporation or other entity. The foregoing provision, however, shall not
prohibit Employee from investing in securities of any corporation whose
securities are listed on a national securities exchange or traded in the
over-the-counter market if Employee shall be the owner, beneficially or of
record, of less than five percent (5%) of any class of the stock of such
corporation.

          (D)  Extension of Period. If Employee violates this restrictive
covenant and Employer brings legal action for injunctive or other relief,
Employer shall not, as a result of the time involved in obtaining such relief,
be deprived of the benefit of the full period of the restrictive covenant.
Accordingly, the restrictive covenant shall be deemed to have the duration
specified in subparagraph (A) hereof, computed from the date such relief is
granted but reduced by the time expired between the date the period of
restriction began to run and the date of the first violation of the covenant by
Employee.

          (E)  Reformation or Judicial Modification. Employee acknowledges and
agrees that the duration and geographical restrictions set forth herein have
been specifically discussed and negotiated and are reasonable in view of all the
facts and circumstances known to Employee. Nevertheless, if any court shall
determine that such duration or geographical limits are unenforceable, the
restrictions set forth herein shall be deemed modified to apply for the maximum
duration and geographical area which are reasonable in view of all the facts and
circumstances, and the Agreement shall be reformed to that extent.

     8.   REMEDIES OF EMPLOYER. As an employee of Employer, Employee may have
access to customer lists, trade secrets and other confidential information of
Employer. Moreover, his continued employment will be instrumental to the
continuity and development of Employer's business. Employee therefore
acknowledges that the restrictions contained in Paragraphs 6 and 7 of this
agreement are a reasonable and necessary protection of the legitimate interests
of Employer, that any violation of them could cause substantial injury to
Employer and that Employer would not have entered into this Agreement with
Employee without receiving the additional consideration of Employee's binding
himself to said restrictions. In the event of any violation of the said
restrictions, Employer shall be entitled, in addition to any other remedy, to
preliminary and permanent injunctive relief.

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     9.   SURRENDER OF BOOKS AND RECORDS. Employee acknowledges that all files,
lists, books, records, literature, products and any other materials owned by
Employer or its affiliates or used by them in connection with the conduct of
their business, shall at all times remain the property of Employer and its
affiliates and that upon termination of employment hereunder, irrespective of
the time, manner or cause of said termination, Employee will surrender to
Employer and its affiliates all such lists, books, records, literature,
products and other materials.

     10.  SEVERABILITY. The invalidity or unenforceability of any particular
provision, or any part thereof, of this Agreement shall not affect the other
provisions hereof and this Agreement shall be continued in all respects as if
such invalid or unenforceable provision were omitted.

     11.  NOTICES. All notices, requests, demands and other communications
required under this Agreement shall be in writing and shall be deemed duly
given and received (i) if personally delivered, on the date of delivery; (ii)
if mailed, three (3) days after deposit in the United States mail, registered
or certified, return receipt requested, postage prepaid and addressed as
provided below, or (iii) if by a courier delivery service providing overnight
or "next day" delivery, on the next business day after deposit with such
service, addressed as follows:

     If to Employer:     Alliance Medical Corporation
                         3010 North 2nd Street, Suite 110
                         Phoenix, Arizona 85012

     Copy to:            Mr. Michael Perry
                         Jennings, Strouss & Salmon
                         Two North Central Avenue
                         Phoenix, Arizona 85004

     If to Employee:     David A. Amrhein
                         7315 S. Hazelton Lane
                         Tempe, AZ 85283

Any party may change its above-designated address by giving the other party
written notice of such change in the manner set forth herein.

     12.  SUCCESSORS IN INTEREST. This Agreement shall be binding upon, inure
to the benefit of, and be enforceable by and against the respective heirs,
executors, administrators, personal representatives, successors and permitted
assigns of any of the parties to this Agreement.

     13.  WAIVER. No waiver of any of the provisions of this Agreement shall be
deemed, or shall constitute, a waiver of any other provisions hereof (whether
or not similar) nor shall such waiver constitute a continuing waiver, and no
waiver shall be binding unless executed in writing by the party making the
waiver.

     14.  GOVERNING LAW; JURISDICTION. Except as expressly provided herein,
this Agreement shall be construed in accordance with, and governed by, the laws
of the State of Arizona, without regard to the application of conflicts of law
principles. Except in respect of an action commenced by a third party in
another jurisdiction, the parties agree that any legal suit,



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action or proceeding arising out of or relating to this Agreement must be
instituted in the State or Federal court in the City of Phoenix, Maricopa
County, State of Arizona, and they hereby irrevocably submit to the
jurisdiction of any such court.

     15.  ATTORNEY'S FEES. In the event an action or suit is brought by any
party hereto to enforce the terms of this Agreement, the prevailing party shall
be entitled to the payment of reasonable attorneys' fees and costs, as
determined by the judge of the court.

     16.  ENTIRE AGREEMENT; MODIFICATIONS. This Agreement constitutes the
entire agreement among the parties and supercedes all prior and contemporaneous
agreements and understandings of the parties with respect to the subject matter
hereof. No supplement, modification or amendment of this Agreement shall be
binding and enforceable unless executed in written by the parties hereto.

     17.  HEADINGS. Headings contained in this Agreement are inserted only as a
matter of convenience and in no way define, limit, extend or describe the scope
of this Agreement or of any provisions hereof.

     18.  COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
day and year first above written.


"EMPLOYER"                              "EMPLOYEE"

ALLIANCE MEDICAL CORPORATION

By:
   ----------------------------         -------------------------------
       R.M. (RICK) FERREIRA                   DAVID A. AMRHEIN

Its: CHIEF EXECUTIVE OFFICER
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