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                                                                 Exhibit 10.12
                      SEPARATION AND SETTLEMENT AGREEMENT

     THIS SEPARATION AND SETTLEMENT AGREEMENT ("Agreement") is entered into on
December 8, 1998, between PHYMATRIX CORP., ("Company") and ROBERT A. MILLER
("Employee").

     WHEREAS, Employee has been employed by the Company as President and has
served as a member of its Board of Directors; and 

     WHEREAS, the parties hereto wish to enter into this Agreement for the
purpose of providing a full and final settlement and resolution of all matters
arising out of or pertaining to Employee's employment relationship with the
Company, his service as a member of the Company's Board of Directors and the
termination of Employee's relationships with the Company, whether past, present,
or future;

     THEREFORE, in consideration of the mutual promises and undertakings 
contained herein and for such other good and valuable consideration, the 
receipt and sufficiency of which are hereby acknowledged, the parties do 
hereby agree as follows:

     1.  TERMINATION OF EMPLOYMENT:  Employee's employment with the Company 
shall terminate on December 8, 1988 ("Termination Date"), and he hereby 
resigns all of his positions with the Company and its subsidiaries and he 
hereby resigns his seat on the Company's Board of Directors.

     2.  COMPENSATION: In consideration for execution and compliance with this
Agreement, Employee shall receive a severance payment in the amount of
Six-Hundred Seventeen Thousand Five-Hundred Twenty-Eight Dollars ($617,528.00),
less applicable taxes and statutory deductions, which amount includes all
amounts due to Employee based on his employment with the Company

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(including its subsidiaries), including without limitation, all compensation 
payable pursuant to any written agreement, all vacation pay, sick pay, 
prerequisites and bonuses. The severance payment shall be payable Three 
Hundred Seventy-Five Thousand Dollars ($375,000.00) at the time of execution 
of this Agreement with the remaining Two Hundred Forty-Two Thousand Five 
Hundred Twenty-Eight Dollars ($242,528.00) plus the Interest Factor payable 
in four (4) equal monthly payments of principal and interest beginning on 
January 1, 1999 and ending April 1, 1999.  The Interest Factor shall be equal 
to the Prime Rate of Interest charged by Nations Bank on the date of 
execution of this Agreement plus two percent (2%) per annum, multiplied by 
the unpaid portion of the severance pay payable to employee over the 
aforementioned six (6) month period. The Interest Factor shall be adjusted as 
payments are made under this Agreement; in which case, the portion of the 
four (4) equal payments of interest shall be adjusted to reflect the same. 
These payments may be accelerated at the option of the Company; provided 
however, that in the event that the Company generates over Twenty Million 
Dollars ($20,000,000.00) of gross sales proceeds from the sale or exchange of 
any of its assets after the date of execution of this Agreement and prior to 
April 1, 1999, there shall be an immediate acceleration of the unpaid 
severance pay due to Employee under this Agreement; in which case, such 
amount shall be immediately payable to the Employee.  Any acceleration of 
payment due under this Agreement shall offset the latest required payment due 
to Employee under this Agreement. Without limiting the foregoing, Employee 
acknowledges and agrees that the foregoing severance payment is provided in 
excess of any payment or other thing of value to which he is already entitled 
or would be entitled if he did not sign this Agreement.

     In connection with the termination of Employee's employment, Employee's
right to participate in and receive benefit under any employee benefit or
fringe benefit plan, program or

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arrangement established, maintained or contributed to by the Company (or its 
subsidiaries) shall terminate as of the effective date of this Agreement 
subject to the Employee's rights, if any, to continue coverage under a group 
health plan maintained by the Company pursuant to the Federal Consolidated 
Omnibus Budget Reconciliation Act of 1985 ("COBRA"), if any, provided, 
however, that Employee shall be solely responsible for all costs associated 
with such COBRA coverage (including all costs associated with any qualified 
beneficiaries who elect to continue coverage under COBRA who are or were 
dependents of the Employee) including, without limitation, all preliminary 
costs for such COBRA coverage.

     3.   COMPANY PROPERTY:   Employee shall return to the Company all 
property, equipment, records, correspondence, manuals, documents, files, 
keys, computer disks, computer programs, data and any other information 
(whether originals, copies or extracts) belonging to the Company, whether 
maintained by Employee in the facilities of the Company, at Employee's home, 
or at any other location, and Employee shall not retain any copies or 
reproductions of any confidential information of the Company. Employee 
further represents and warrants that he has not, and will not, destroy, 
delete, erase, or alter, without the express written permission of the 
Company, any information or data currently used by the Company in the course 
of its business. Employee agrees to provide the Company with the passwords to 
access all files maintained on the Company's computer system.

     Notwithstanding the foregoing, Employee shall have the right to keep all 
of the furniture and other personal property located in his office, including 
but not limited to, computers and their accessories, as well as all of the 
furniture and other property utilized by his assistant at her work station, 
including but not limited to, her computer, printers, facsimile and other 
accessories. In addition, Employee or any of his affiliates shall also have 
the right to hire Ms. Laura Walenius.

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     4.   RELEASE OF CLAIMS AGAINST THE COMPANY AND ITS AFFILIATES.

          a.   Employee accepts the terms of this Agreement in full, final 
and complete satisfaction and settlement of any and all claims which in any 
way relate or pertain to or arise out of (i) him employment with the Company 
(including its subsidiaries), the terms and conditions of such employment and 
the termination of that employment or (ii) his dealings with, and any 
positions held with respect to the Company and its subsidiaries, including 
without limitation, his membership on the Company's Board of Directors. 
Without limiting the foregoing, in consideration of the Company's promise to 
pay the amount specified in Paragraph 3 of this Agreement, Employee hereby 
waives, covenants not to sue and releases the Company and any and all parent, 
subsidiary or affiliated corporations or business entities and any and all 
respective past or present employees, officers, agents, directors, 
shareholders, representatives and attorneys of the foregoing and others 
acting for or on behalf of the foregoing (the "Releases") from all past, 
present or future claims, actions, rights or benefits of whatever nature or 
description both in law and in equity from the beginning of time through and 
including the date of execution of this Agreement ("Claims") including 
without limitation Claims arising out of, based upon or connected with his 
employment, the terms and conditions of his employment or the termination of 
Employment under the Age Discrimination in Employment Act of 1967, as 
amended, (the "ADEA") attorney's fees and expenses and any claim to stock 
option(s), change-in-control bonuses, or bonus payments, past, present or 
future, whether accrued or not, and any other document executed 
contemporaneous with this Agreement; provided, however, that this waiver 
shall not release any rights or claims that may arise under the ADEA after 
the execution of this Agreement. The Company acknowledges that nothing in 
this release encompasses, covers, alters,

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limits or bars the right of Employee to pursue claims against the Company for 
breach of paragraphs 3, 7, 11, or 12 of this Agreement or the Physician 
Practice Consulting Agreement.

      b. In the event the Company fails to make any of its payment 
obligations when due under the Separation and Settlement Agreement as well as 
its obligations to RAM Advisors, Inc. under the Consulting Agreement being 
executed contemporaneously with the execution of this Agreement, then, 
notwithstanding the provisions of paragraph 4(a) or any other language in 
this Agreement to the contrary until such payments are made, the Company and 
the Employee shall each retain the absolute right to take all proper and 
necessary actions to satisfy any and all claims or rights of the Employee or 
the Company, as the case may be.

     5. Employee acknowledges the following: (i) he has been given a full 
and fair opportunity to consider this Agreement, and understands its terms; 
(ii) he has been advised in writing to consult with an attorney, and he has 
in fact consulted with an attorney before signing this Agreement; (iii) he 
was given a period of twenty-one days from the date he was furnished with 
this Agreement within which to consider execution of the Agreement; and (iv) 
should be decide to sign the Agreement, Employee has seven days following the 
signing to revoke the Agreement (the "Revocation Period"). The Agreement will 
not become effective and enforceable until the Revocation Period has 
expired. Employee acknowledges that if he either decides not to sign this 
Agreement, or if he signs it and elects to revoke it during the Revocation 
Period, then this Agreement shall be null and void.

     6. RELEASE OF CLAIMS AGAINST EMPLOYEE.

          a. The Company and its subsidiaries, successors and assigns accept 
the terms of this Agreement in full, final and complete satisfaction and 
settlement of any and all claims which in any way relate or pertain to or 
arise out of Employee's employment with the Company 


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and its subsidiaries and Employee's service as a member of the Company's 
Board of Directors. Accordingly, the Company hereby releases Employee from 
all past, present to future claims, actions, rights or benefits of whatever 
nature or description, including claims for attorneys' fees and expenses, 
past or future, whether accrued or not, from the beginning of time through 
and including the date of the execution of this Agreement.

          b. The Company and its subsidiaries, successors and assigns agree 
to indemnify and hold harmless the Employee and his successors and assigns at 
all times after the date of this Agreement from and against any and all loss, 
cost, liability damage and expenses (including legal and other expenses 
incident thereto), to the fullest extent permitted by Delaware law, arising 
out of or resulting from (i) any inaccuracy, misrepresentation or breach of 
any representation, warranty, covenant or agreement of such party under this 
Agreement; (ii) any causes of action or claims brought by, in the name of or 
on behalf of any person or entity with respect to any Prior Related Event as 
defined below; (iii) any cause of action relating to the negotiation, 
execution and consummation of this Agreement; and, (iv) any claims, actions, 
suits, proceedings, demands, assessments, judgments, costs and expenses 
(including legal and other expenses incident thereto) incident to any of the 
foregoing.

          c. As used herein, "Prior Related Event: shall mean any 
transaction, event, circumstance, action, failure to act, or occurrence of 
any sort or type related in any way to (i) the business and employment 
relationships and activities between Employee and the Company prior to the 
date hereof, or (ii) the relationships relating to the matters covered by 
this Agreement prior to the date hereof, provided however, that a Prior 
Related Event does not include any act of fraud or wilful misconduct that are 
legally determined to have been caused by the Employee.

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          d. It is further understood and agreed that this document is 
intended to be a total accord, settlement, and satisfaction of any and all 
claims which the Company has and may have had against Employee. The Company 
further acknowledges and understands that there are no limitations or 
covenants which in any way restrict the future business activity of Employee.

     7. CONFIDENTIALITY.

          a. Employee and the Company agree for a period of two (2) years 
from the date of this Agreement to maintain in strict confidence the terms of 
this Agreement and the amount of the payments specified in Paragraph 2 and 
that each of them will not disclose the terms of this Agreement or the amount 
of said payments to anyone unless required by law including all applicable 
securities laws and regulations; provided that, Employee may disclose to his 
accountants, attorneys, and tax advisors or financial consultants such 
information as may be necessary for tax planning or the preparation of tax 
returns.

          b. Employee and the Company further agree that for a period of two 
(2) years from the date of this Agreement that Employee shall not disclose to 
any third party any confidential or non-public information relating to the 
Company and the Company shall not disclose to any third party any 
confidential or non-public information relating to Employee ("Information") 
regardless of the source, without the written consent of the party to which 
such information relates (the "Information Party"). In the event any party to 
this Agreement is requested or required to disclose any of the Information, 
he, she or it will provide the Information Parties with notice of such 
request or requirement so that the Information Party may seek an appropriate 
protective order or waive compliance with the terms of this Agreement. If any 
party to this Agreement is, in the opinion of counsel, compelled to disclose 
any of the Information, he, she or it will cooperate with the Information 
Party to obtain assurances that confidential treatment will be accorded to the


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disclosed Information. Each of the parties agree that in the event of any 
actual or threatened breach of the confidentiality provisions of this 
paragraph, in addition to whatever other remedies may be available to such 
party(ies) such party(ies) shall be entitled to an injunction or other 
equitable relief to prevent such breach and to attorney's fees incurred 
in the successful prosecution of any civil action or other legal proceedings
from the breach of these provisions.

     8. NON-SOLICITATION. Miller agrees for a period of two (2) years 
following the completion of the Physician Practice Management Consulting 
Agreement that he shall not solicit, induce or attempt to solicit or hire any 
current employee of the Company who is engaged in the direct delivery of 
clinical trial site management organization services.

     9. NON-COMPETITION. Miller agrees that for a period of two (2) years 
commencing upon the completion of the Physician Practice Management 
Consulting Agreement that he will not engage in any business or employment 
which is in direct competition with the Company's direct delivery of clinical 
trial site management organization services.

     10. NON-DISPARAGEMENT. Employee agrees that he will not at any time 
denigrate, degrade, ridicule, intentionally criticize or make negative 
remarks about the Company or any of its affiliates or any of their respective 
employees, officers, directors, agents or representatives. The Company agrees 
that it will not at any time denigrate, degrade, ridicule, intentionally 
criticize or make negative remarks about Employee. If called upon, the 
Company will direct all inquiries to Mr. Abraham D. Gosman, to provide a 
favorable reference for Employee.

     11. PRESS RELEASE. The parties agree that they will prepare a form of 
press release announcing the Employee's resignation from the Company and that 
no statement will be made or issued concerning the Employee's resignation 
from the Company until a form of release has been jointly approved by the 
parties to this Agreement.

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     12.   Availability for Work:   Employee agrees that he shall be 
available to the Company or its designee, as reasonably requested, to assist 
in the transition of Company matters for which Employee had responsibility 
during the term of his employment.

     13.   Severability.   Should any provision of this Agreement be declared 
or determined by any court of competent jurisdiction to be unenforceable or 
invalid for any reason, the validity of the remaining parts, terms and 
provisions of this Agreement shall not be affected thereby and the invalid or 
unenforceable part, term or provision shall be deemed not to be part of the 
Agreement.

     14.   Arbitration:   Any dispute, controversy, claim or disagreement 
arising out of or relating to this Agreement in any way shall be conclusively 
settled by arbitration to be held in the City of West Palm Beach, Florida in 
accordance with the procedural rules of the American Arbitration Association. 
Judgement upon the decision and award of the arbitrator(s) may be entered in 
any court having jurisdiction thereof. In addition, the parties agree that the 
arbitrator(s) shall have the exclusive power to consider and issue requests 
for injunctive relief to prevent any breach of this Agreement or to enforce 
specifically the terms and provisions of this Agreement. The costs, 
attorney's fees and expenses of such arbitration that are incurred by the 
prevailing party shall be awarded by the arbitrator to the prevailing party. 
The parties specifically waive all rights to commence or prosecute (or cause 
to commence or prosecute) any action in a court or other judicial forum with 
respect to this Agreement, any Claims, or any matter addressed in this 
Agreement. Notwithstanding the foregoing, in the event the Company fails to 
timely make any payment required to be made to Employee under this Agreement, 
interest on the unpaid portion shall accrue at the rate of fifteen percent 
(15%) per annum and Employee shall be entitled to costs and attorney's fees 
incurred in connection with collection of any payment which was not timely

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made to it under this Agreement.

     15.   Governing Law:   This Agreement shall be exclusively subject to 
the law of the State of Florida.

     16.   Whole Agreement:   This Agreement constitutes the entire Agreement 
between the parties and embodies and supersedes any agreements or 
understandings, whether oral or written. It is further understood and agreed 
that this Agreement may not be changed, altered or amended except in a 
subsequent writing signed by each of the parties hereto. This agreement may 
be executed in multiple originals.

     17.   Waiver of Rights:   If in one or more instances, either party 
fails to insist that the other party perform any of the terms of this 
Agreement, such failure shall not be construed as a waiver by such party of 
any past, present or future right granted under this Agreement, and the 
obligations of both parties under this Agreement shall continue in full force 
and effect.

     18.   Acknowledgment:   Employee and the Company acknowledge and 
represent that they have each read or caused to be read this Agreement and 
that each understands it fully and signs it voluntarily. Employee further 
acknowledges that nothing contained in this Agreement or the payment of the 
sums referred to above shall be construed as an admission of liability on the 
part of the Company or Employee, all such liability being expressly denied.

     19.   Notices:   All notices and other communications required or 
permitted under this Agreement shall be in writing and shall be (as elected 
by the person giving such notice) hand delivered by messenger or overnight 
courier service or mailed by U.S. certified mail (postage prepaid), return 
receipt requested addressed to the parties as follows:

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If to PhyMatrix Corp.:    Abraham D. Gosman
                          513 North Country Road
                          Palm Beach, FL 33480

with a copy to:           Michael Bohnen, Esq.
                          Nutter McClennen & Fish, LLP
                          One International Place
                          Boston, MA 02110-2699

If to Robert A. Miller:   Robert A. Miller
                          607 S. Beach Road
                          Tequesta, Florida 33469

with a copy to:           Richard B. Comiter, P.A.
                          Richard B. Comiter, Esq.
                          222 Lakeview Avenue, Suite 800
                          West Palm Beach, FL 33401

                          The Falk Law Firm, pllc
                          James H. Falk, Jr.
                          2445 M Street, NW, Suite 260
                          Washington, D.C. 20037

or to such other address as either party may designate by notice complying 
with the terms hereof. Each such notice shall be deemed delivered (a) on the 
date delivered if by personal or overnight delivery, or (b) on the date upon 
which the return receipt is signed, delivery is refused, or the notice is 
designated by the postal authorities as not deliverable, as the case may be, 
if mailed. Any notice required or permitted to be given under this Agreement 
shall be sufficient if in writing and sent by registered or certified mail to 
the principal office of the recipient.


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     IN WITNESS WHEREOF, the undersigned hereunto set their hands on the 
dates shown below.


                                      ROBERT A. MILLER

                                              /s/ Robert A. Miller
                                      ----------------------------------------


                                      PHYMATRIX CORP.

                                      By:          /s/ Abraham Gosman
                                          ------------------------------------


DATED:         12/8/98
       -----------------------


SEEN AND APPROVED:


      /s/ Abraham Gosman
------------------------------
ABRAHAM GOSMAN

           12/8/98
------------------------------
DATE


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