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                                                                  EXHIBIT 10.58





                    [RAUSCHER PIERCE & CLARK LETTERHEAD]


23 October, 1996



Bruce Barrett Esq
President and Chief Executive Officer
Somanetics Corporation
1653 E. Maple Road
Troy
Michigan 48083-4208
USA



                                                       PRIVATE AND CONFIDENTIAL



Dear Bruce,

You have indicated that Somanetics Corporation (the "Company") desires to
retain Rauscher Pierce & Clark, Inc. and its wholly-owned subsidiary, Rauscher
Pierce & Clark Limited (together, the "Placement Agent") to serve as the
Company's exclusive financial advisor in connection with a proposed private
placement of securities (the "Placement").  The securities to be placed in the
Placement (the "Securities") will consist of up to 1,500,000 of newly issued
shares of the Company or such other securities as may be subsequently agreed
between the Company and the Placement Agent.  The Placement will be structured
and conducted in all respects to meet all the requirements of Regulation S
under the Securities Act of 1933, as amended (the "Securities Act").  This
agreement (the "Agreement") sets forth (i) the services to be provided by the
Placement Agent in connection with this Placement; (ii) the professional fees
and expenses payable to the Placement Agent in exchange for their services; and
(iii) general terms and conditions of the engagement.


In connection with the proposed Placement, the Company and the Placement Agent
hereby agree as follows:


1.   The Company hereby appoints the Placement Agent as its exclusive agent to
     arrange the Placement on a "best efforts" basis during the 30-day period
     commencing on the date hereof (the "Offering Period"), which period may be
     extended by mutual written agreement of the parties hereto.  Subject to
     the terms and conditions herein set forth, the Placement Agent accepts
     such appointment and shall endeavour to identify sources for the
     Placement. (each, a "Source") Such agency shall continue until the earlier
     to





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     occur of termination of the Offering Period or termination by the Company
     or the Placement Agent of this Agreement upon ten days' prior notice,
     except that in any event, the Placement Agent's agency shall terminate at
     the date the Placement has been closed.  In the event the
     arrangement of the Placement is commenced and this Agreement is terminated
     by any party hereto for any reason or indications of interest for the
     Placement are not received by the end of the Offering Period, the
     Placement Agent's agency and this Agreement shall terminate without
     further obligation of either the Placement Agent or the Company to the
     other except as provided in this Paragraph I and in Paragraphs 3, 4 and 6
     below.  The Company shall have the right to reject any and all proposed
     sources of the Placement as well as the terms, amounts and provisions
     which may be proposed for the Placement for any reason the Company deems
     reasonable in the exercise of its sole and arbitrary discretion.
     Notwithstanding the foregoing, in the event that a potential Source is
     contacted and introduced, as provided herein, by the Placement Agent to
     the Company during the Offering Period and the Source provides the
     Placement or an alternative financing arrangement to the Company after the
     expiration of the Offering Period, at any time during one (1) year from
     the date of commencement of the Offering Period, the Placement Agent shall
     be entitled to the same fees provided for below with respect to such
     arrangement as if the arrangement had occurred during the Offering Period;
     provided that such fees shall not be payable in connection with any of the
     following: (i) the issuance or sale of any options or warrants to any
     employee, executive, officer, director, agent, advisor or consultant to
     the Company, (ii) the issuance or sale by the Company of any capital stock
     pursuant to (A) the exercise of any of the foregoing options or warrants,
     (B) the exercise of any options or warrants previously issued and
     outstanding or authorised on the closing date of the Placement, or (C) the
     issuance or sale by the Company of any options, warrants, convertible
     securities or capital stock pursuant to anti-dilution provisions
     applicable to the Company or its securities Further, if the Company elects
     to pursue an alternative financial arrangement, merger or other
     transaction in lieu of the placement during the Offering Period and the
     Placement Agent has identified investors within the Offering Period who
     are qualified subscribers under Regulation S and are ready, willing and
     able to purchase the Securities on or before the end of the Offering
     Period on such terms and conditions as are acceptable to the Company, or
     decides not to proceed with the closing for the Placement for any other
     reason, then the Company shall pay the full fees provided for below as if
     the Placement had been completed.


2.   The Placement Agent will assist and advise the Company through all phases
     of the placement process.  Services to be provided will include without
     limitation: (i) assisting the Company with preparation of a Placement
     Memorandum for the arrangement of the Placement which shall contain such
     information as we may mutually determine may be required; (ii)
     identification of prospective Sources; (iii) distribution of the Placement
     Memorandum and other offering documents to and contact of prospective
     Sources following approval by the Company of such placement memorandum and
     of such distribution; (iv) arranging meetings and accompanying the Company
     in meeting with prospective Sources in Europe (v) evaluating preliminary
     indications of interest, and assisting Sources in conducting due
     diligence; (vi) assisting the Company and its counsel through the process
     of negotiating and drafting definitive documents; and (vii) assisting in
     the closing.  The Placement Agent shall not, in fulfilling its obligations
     hereunder, act as underwriter for the Securities, and is in no way
     obligated, directly or



                                                        Rauscher Pierce & Clark


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indirectly, to advance its own funds to purchase any of the Securities  
subscribed for in the Placement.


3.   In exchange for the services set forth in Paragraph 2, the Company agrees
     to reimburse the Placement Agent for all reasonable out-of-pocket expenses
     incurred on this project at the request of the Company, including any
     reasonable legal expenses; provided, however, that such expenses for the   
     Placement Agent and for the Placement Agent's legal counsel shall not
     exceed $20,000 without the Company's prior consent, excluding
     disbursements of such legal counsel and travel by the Placement Agent
     agreed in advance with the Company.  Such expense reimbursement is not
     contingent upon the successful completion of the transaction contemplated
     hereunder, and shall be payable as incurred by the Placement Agent and
     billed to the Company from time to time.


4.   Upon the closing of the Placement to one or more sources and the receipt
     by the Company of the proceeds thereof, the Company shall pay the
     Placement Agent a fee ("Placement Fee") equal to 10% of the aggregate
     gross proceeds from the Placement.  The Placement Fee shall be payable in
     cash at closing.


5.   (a)       Prior to the sale of Securities pursuant to the Placement to
               any Source or any person advising such Source, they shall
               be furnished information by the I Company pertaining to the
               Company and the terms and conditions of the Placement and
               will be given the opportunity by the Company to ask questions
               and receive answers concerning the Company and the terms and
               conditions of the Placement.


     (b)       The Company agrees that all written information provided to 
               any Source or to the Placement Agent and their agents by the
               Company (the "Written Communications"), and all oral
               communications provided to any Source or the Placement Agent and
               their agents by the Company, will not contain any untrue
               statement of a material fact or omit to state a material fact
               necessary to make the statements, in light of the circumstances
               in which they were made, not misleading as of the point in time
               given.


     (c)       The Company covenants that it shall promptly notify the 
               Placement Agent if, because of the occurrence of any event or
               condition, the passing of time or otherwise, any of the Written
               Communications or any oral communications of the Company and its
               officers or directors to the Placement Agent or any Source which
               relate to the offer and sale of Securities pursuant to the
               Placement contain any untrue statement of a material fact or
               omit to state a material fact necessary to make the
               communications, in light of the circumstances under which they
               were made, not misleading.  The Written Communications (and any
               Oral Communications) shall be amended in form and substance
               satisfactory to the Placement Agent and the Company so that
               after giving effect to such amendment, the Written
               Communications (and attendant oral communications) will not
               contain any untrue statement of a material fact or omit to state
               a material fact necessary to make the statements, in light of
               the circumstances under which they were made, not misleading.



                                                        Rauscher Pierce & Clark



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     (d)       The Company shall furnish or make available to the Placement 
               Agent or its authorised representatives any and all
               documentation and information reasonably requested by the
               Placement Agent in connection with their due diligence
               efforts regarding this Placement.


     (e)       As a primary consideration for this Agreement, the Placement 
               Agent will plan, arrange for and accompany the Company's
               executive officers on a trip to Europe to meet prospective
               Sources whom the Placement Agent shall have identified and
               contacted in advance.


6.   In addition to the amounts which the Company has herein agreed to pay to
     the Placement Agent, the Company shall defend, indemnify, and hold the
     Placement Agent and officers, directors, agents, employees and controlling
     persons harmless against any losses, claims, damages, or liabilities
     (including, without limitation, court costs and reasonable attorneys'
     fees) to which the Placement Agent and officers, directors, agents,
     employees and controlling persons may become subject, as described in
     Schedule I to this Agreement which is to be considered an integral part of
     this Agreement.


7.   Each of the parties understands and agrees that this commitment letter is
     being executed by their respective authorised representatives and is not
     subject to any further approvals or ratification in order to become a
     binding obligation of each of them.


8.   The Company understands that the Placement Agent's engagement hereunder
     may involve work in the United Kingdom which will or may be described as
     "investment business" for the purposes of the UK Financial Services Act
     1986 (the "FSA").  This work will be undertaken by Rauscher Pierce & Clark
     Ltd, which is a member of The Securities and Futures Authority (the
     "SFA").  On the basis of the information the Company has supplied and on
     the basis of the Company's experience and understanding in relation to
     investments, we have categorised the Company as a nonprivate customer.  As
     a consequence of this categorisation, the Company will lose the
     projections afforded to private customers under the SFA Rules, including
     the right to sue Rauscher Pierce & Clark Ltd. for damages under Section 62
     of the FSA and the fight of access to the Customer Arbitration Scheme of
     the SFA; provided, however, that nothing in the foregoing shall act to
     waive any right which the Company may have under any other applicable law
     or under any agreement with the Placement Agent, including, without
     limitation, this Agreement.


This Agreement shall be governed by and constituted in accordance with the laws
of the State of Michigan without regard to the conflict of law provision
thereof, If the foregoing correctly sets forth our mutual understanding of
these arrangements, please so indicate by signing and returning to us the
enclosed copy of this Agreement.



                                                         Rauscher Pierce & Clark



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We are delighted to have this opportunity to assist the Company and we look
forward to committing the resources of Rauscher Pierce & Clark towards the
prompt arrangement of the Placement on the best available terms.



Yours sincerely,

RAUSCHER PIERCE & CLARK, INC.


                                         AGREED TO AND ACCEPTED THIS
By:      [SIG]                
   ----------------------------             25 day of October 1996


RAUSCHER PIERCE & CLARK LIMITED
                                            SOMANETICS CORPORATION



By:      [SIG]              
   ----------------------------

                                         By:          BRUCE BARRETT
                                             ---------------------------------
                                                                 Bruce Barrett  
                                          President and Chief Executive Officer





                                                         Rauscher Pierce & Clark



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                                 SCHEDULE I



1.   The Company agrees to defend, indemnify, and hold the Placement Agent, and
     its respective officers, directors, agents, employees and
     controlling persons (each an "Indemnified Party") harmless from and
     against any losses, claims, damages or liabilities (including, without
     limitation, court costs and reasonable attorneys' fees) to which any such
     Indemnified Party may become subject insofar as the same arises from an
     action which alleges or is based upon any alleged untrue statement of a
     material fact, or omission of a material fact, or any other violation of
     applicable securities' or other laws, rules or regulations by the Company
     or its officers, agents, employees or controlling persons, irrespective of
     the role or concurrent negligence of any such Indemnified Party and to
     reimburse any such Indemnified Party for any legal or other expenses
     reasonably incurred by them in connection with investigating, settling, or
     defending any action or claim in connection therewith (including, without
     limitation, court costs and reasonable attorneys' fees)- provided,
     however, that the Company shall not be liable in any such case to the
     extent that any such loss, claim, damage, or liability is found in a final
     judgement of a court of competent jurisdiction to have resulted from any
     such Indemnified Party's gross negligence or bad faith in performing their
     services hereunder.  If for any reason the foregoing indemnification is
     unavailable to an Indemnified Party or insufficient to hold an Indemnified
     Party harmless, then the Company shall contribute to the amount paid or
     payable by that Indemnified Party as a result of such loss, claim, damage,
     or liability in such proportion as is appropriate to reflect not only the
     relative benefits received by the Company on the one hand and the
     Indemnified Party on the other hand but also the relative fault of the
     Company and that Indemnified Party, as well as any relevant equitable
     considerations.  The Company agrees to reimburse an Indemnified Party
     within ten days after presentation of any statement by that Indemnified
     Party of all reasonable expenses (including without limitation of the
     generality of the foregoing, fees and expenses of attorneys selected by
     each Indemnified Party) incurred in connection with any testimony the
     Indemnified Party or its employees are required to give (in court, before
     a regulatory agency, by deposition, or otherwise) in any regulatory or
     court proceeding (including depositions), whether or not the Indemnified
     Party is a party, and which related directly or indirectly to the proposed
     Placement.



2.   With respect to the foregoing Paragraph I of the indemnification, the
     Company agrees that no Indemnified Party shall be deemed to have been
     grossly negligent for reasonably relying upon any written untrue statement
     or alleged omission of a material fact necessary to make the statements,
     in light of the circumstances in which made, not misleading, contained in
     or omitted from any information provided to any Indemnified Party by or on
     behalf of the Company (including, without limitation of the generality of
     the foregoing, any accountant or attorney employed or retained by the
     Company).  The indemnification provided in the foregoing Paragraph I
     hereof shall extend upon the same terms and conditions to each person, if
     any, who may be deemed to control any Indemnified Party.



                                                         Rauscher Pierce & Clark



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3.   In the event any action (with respect to which indemnity or reimbursement
     from the Company may be sought by any Indemnified Party on account of
     agreements contained herein) shall be brought or threatened against an
     Indemnified Party, prompt notice will be given to the Company in writing
     of such action, together with a copy of all papers served on, or received
     by, such Indemnified Party in connection with such action provided that
     failure to give such notice shall not affect such Indemnified Party's
     right under these indemnification provisions, unless, and only to the
     extent that, such failure results in the Company's forfeiture of
     substantive rights or defenses.  If such an event occurs, the Company
     shall assume the defense of such action, including the employment of
     counsel and the payment of all expenses.  Each Indemnified Party shall
     have the right to employ separate counsel in any such action and to
     participate in the defense thereof, but the fees and expenses of such
     counsel shall be at the expense of each such Indemnified Party unless (a)
     the employment thereof has been specifically authorised by the Company in
     writing (b) the Company has failed to assume the defense and employ
     counsel or (c) the named parties, or parties threatened to be named, to
     any such action (including any impleaded parties or parties threatened to
     be impleaded) include both such Indemnified Party and the Company, and the
     Company has been advised by such counsel that there may be one or more
     legal defenses available to them which are different from or additional to
     those available to the Company (in which cases each Indemnified Party with
     a different legal defense from those of other Indemnified Parties with
     their own counsel shall have the right to employ its own counsel and in
     such cases any reasonable fees and expenses of such counsel shall be paid
     by the Company).  The Company shall not be liable for any such action or
     proceeding effected without its written consent.



                                                         Rauscher Pierce & Clark