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                                                                   EXHIBIT 10.4


                                ALLIANCE MEDICAL

                              EMPLOYMENT AGREEMENT

         The Agreement made this 10th day of August 1999 between ALLIANCE
MEDICAL CORPORATION ("Employer") and TIM EINWECHTER ("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 August 16th, 1999 and shall
terminate as provided in paragraph 5.

         2. DUTIES. Employee is employed in the capacity of CHIEF FINANCIAL
OFFICER and 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
Thirty-Eight Thousand Dollars ($138,000) 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 twenty-five percent (25%) of the then current annual salary, paid
quarterly in arrears. 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) Car allowance at $500 per month;
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                  (e) 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;

                  (f) Be reimbursed by Employer for any reasonable expenses
incurred in conjunction with his employment within thirty (30) days of
submitting same. Employee shall present to Employer an itemized written account
of expenses within thirty (30) days after they have been incurred. Employee
shall not be reimbursed 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.
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         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.

                  (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
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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.

         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:   PERSONAL & CONFIDENTIAL
                           Tim Einwechter
                           P.O.  Box 3723
                           Carefree, Arizona 85377
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         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, 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. ATTORNEYS' 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.
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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement on
the day and year first above written.

"EMPLOYER"                              "EMPLOYEE"

ALLIANCE MEDICAL CORPORATION


By: /s/ Ricardo M. Ferreira             /s/ Tim Einwechter
    -------------------------           -------------------------
      R. M. (Rick) Ferreira                 Tim Einwechter

Its:  Chief Executive Officer