EXHIBIT 10.21

STOCK PURCHASE AGREEMENT

Endocardial
Solutions, Inc.
1350 Energy Lane, Suite 110
St. Paul, Minnesota 55108

The
undersigned (the "Investor"), hereby confirms its agreement with you as follows:

1.This Stock Purchase Agreement (the "Agreement") is made as of the date set
forth below among Endocardial Solutions, Inc., a Delaware corporation (the "Company"), and the Investor.

2.The Company has authorized the sale and issuance of up to 3,097,000 shares (the
"Shares") of common stock of the Company, $.01 par value per share (the "Common Stock"), to certain
investors in a private placement (the "Offering").

3.The Company and the Investor agree that the Investor will purchase from the Company and the Company will issue and sell to
the Investor            Shares at a purchase price of $2.75 per Share, or an aggregate purchase price of $            , pursuant
to the Terms and Conditions for Purchase of Shares attached
hereto as Annex I and incorporated herein by this reference as if fully set forth herein. Unless otherwise requested by the Investor in Exhibit A, certificates representing the Shares purchased
by the Investor will be registered in the Investor's name and address as set forth below.

4.The Investor represents that, except as set forth below, (a) it has had no position, office or other material
relationship within the past three years with the Company or its affiliates, (b) neither it, nor any group of which it is a member or to which it is related, beneficially owns (including the
right to acquire or vote) any securities of the Company and (c) it has no direct or indirect affiliation or association with any National Association of Securities Dealers, Inc.
("NASD") member. Exceptions:

|(If no exceptions, write "none." If left blank, response will be deemed to be "none.")
|--------------------------------------------------------------------------------------

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Please
confirm that the foregoing correctly sets forth the agreement between us by signing in the space provided below for that purpose.

|                                                 |  |  | Dated as of:, 200
|------------------------------------------------ |  |  | -----------------
|                                                 |  |  |                  
|                                                 |  |  | "INVESTOR"       
|                                                 |  |  | By:              
|                                                 |  |  |                  
|                                                 |  |  | Print Name:      
|                                                 |  |  |                  
|                                                 |  |  | Title:           
|                                                 |  |  |                  
|                                                 |  |  | Address:         
|                                                 |  |  |                  
|                                                 |  |  |                  
|AGREED AND ACCEPTED:
Endocardial Solutions, Inc. |  |  |                  
|By:                                              |  |  |                  
|                                                 |  |  |                  
|Title:                                           |  |  |                  
|                                                 |  |  |                  

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ANNEX I        TERMS AND CONDITIONS FOR PURCHASE OF SHARES

1.    Agreement to Sell and Purchase the Shares; Subscription Date.



The
Company shall indemnify and hold harmless the Investor from and against all fees, commissions or other payments owing by the Company to the Placement Agent or any other person or
firm acting on behalf of the Company hereunder.

2.    Delivery of the Shares at Closing.The completion of the purchase and sale of the Shares (the
"Closing") shall occur at a place and time, no later than January 7, 2003 (the "Closing Date"),
to be specified by the Company and the Placement Agent, and of which the Investors will be notified in advance by the Placement Agent. At the Closing, the Company shall deliver to the Investor one or
more stock certificates representing the number of Shares set forth in paragraph 3 of the Stock Purchase Agreement, each such certificate to be registered in the name of the Investor or, if so
indicated on the Stock Certificate Questionnaire attached hereto as Exhibit A, in the name of a nominee designated by the Investor provided that, if requested by the Investor, stock
certificates representing such Shares shall be delivered in escrow to such Investor's agent prior to the Closing, to be held until the completion of the Closing. In addition, on or prior to the
Closing Date, the Company shall cause counsel to the Company to deliver to the Investors a legal opinion substantially in the form attached hereto as Exhibit D.

The
Company's obligation to issue and sell the Shares to the Investor shall be subject to the following conditions, any one or more of which may be waived by the Company:
(a) receipt by the Company of a certified bank check or wire transfer of funds in the full amount of the purchase price for the Shares being purchased hereunder as set forth in
paragraph 3 of the Stock Purchase Agreement; (b) completion of purchases and sales under the Agreements with the Other Investors; and (c) the accuracy of the representations and
warranties made by the Investors and the fulfillment of those undertakings of the Investors to be fulfilled prior to the Closing.

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The
Investor's obligation to purchase the Shares shall be subject to the following conditions, any one or more of which may be waived by the Investor: (a) the Company's agreement
to issue and sell, and the Investors' agreement to purchase, on the Closing Date, not less than three million (3,000,000) shares of Common Stock; (b) evidence satisfactory to the Investor that
the Shares have been issued to the Investor (which may be in the form of a facsimile transmission of a copy of the certificate representing the Shares); (c) the delivery to the Investor by
counsel to the Company of a legal opinion in the form attached hereto as Exhibit D; (d) the representations and warranties of the Company contained in Section 3 being true and
correct on and as of such Closing with the same effect as though such representations and warranties had been made on and as of the date of such Closing; (e) the absence of any order, writ,
injunction, judgment or decree that questions the validity of the Agreements or the right of the Company to enter into such Agreements or to consummate the transactions contemplated hereby and
thereby; and (f) the delivery to the Investor by the Secretary or Assistant Secretary of the Company of a certificate stating that the condition specified in part (d) of this paragraph
has been fulfilled.

3.    Representations, Warranties and Covenants of the Company.Except as otherwise described in the Company's
Annual Report on Form 10-K for the year ended December 31, 2001 (and any amendments
thereto filed prior to the date hereof), the Company's Proxy Statement for its 2002 Annual Meeting of Stockholders, or the Company's Quarterly Reports on Form 10-Q for the quarters
ended March 31, 2002, June 30, 2002 and September 30, 2002 (and any amendments thereto filed prior to the date hereof) or any of the Company's Current Reports on
Form 8-K filed since January 1, 2002 (collectively, the "SEC Reports"), the Company hereby represents and warrants to, and
covenants with, the Investor as of the date hereof and the Closing Date, as follows:



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4.    Representations, Warranties and Covenants of the Investor.



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5.    Survival of Representations, Warranties and Agreements.Notwithstanding any investigation made by any party
to this Agreement or by the Placement Agent, all covenants, agreements, representations and warranties made by the Company and the Investor herein shall survive the execution of this Agreement, the
delivery to the Investor of the Shares being purchased and the payment therefor.

6.    Registration of the Shares; Compliance with the Securities Act.



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With
a view to making available to the Investor the benefits of Rule 144 (or its successor rule) and any other rule or regulation of the SEC that may at any time permit the
Investor to sell Shares to the public without registration, the Company covenants and agrees to: (i) make and keep public information available, as those terms are understood and defined in
Rule 144, until the earlier of (A) such date as all of the Investor's Shares may be resold pursuant to Rule 144(k) or any other rule of similar effect or (B) such date as
all of the Investor's Shares shall have been resold; (ii) file with the SEC in a timely manner all reports and other documents required of the Company under the Securities Act and under the
Exchange Act; and (iii) furnish to the Investor upon request, as long as the Investor owns any Shares, (A) a written statement by the Company that it has complied with the reporting
requirements of the Securities Act and the Exchange Act, (B) a copy of the Company's most recent Annual Report on Form 10-K or Quarterly Report on
Form 10-Q, and (C) such other information as

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may be reasonably requested in order to avail the Investor of any rule or regulation of the SEC that permits the selling of any such Shares without registration.

It
shall be a condition precedent to the obligations of the Company to take any action pursuant to this Section 6.1 that the Investor shall furnish to the Company such information
regarding itself, the Shares to be sold by Investor, and the intended method of disposition of such securities as shall be reasonably required to effect the registration of the Shares.

The
Company understands that the Investor disclaims being an underwriter, but the Investor being deemed an underwriter by the SEC shall not relieve the Company of any obligations it has
hereunder.



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In
the event of any sale of the Shares in accordance with this Agreement, the restrictive legend shall be removed and the Company shall issue a certificate without such legend to the
purchaser of any such Shares, if (a) the sale of such Shares is registered under the Registration Statement (including registration pursuant to Rule 416 under the Securities Act);
(b) the holder has provided the Company
with an opinion of counsel, in form, substance and scope customary for opinions of counsel in comparable transactions, to the effect that a public sale or transfer of such Shares may be made without
registration under the Securities Act; or (c) such Shares are sold in compliance with Rule 144 under the Securities Act.



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7.    Notices.All notices, requests, consents and other communications hereunder shall be in writing, shall be
mailed (A) if within domestic United States by first-class registered or certified airmail, or nationally recognized overnight express courier, postage prepaid, or by facsimile, or
(B) if delivered from outside the United States, by International Federal Express (or comparable service) or facsimile, and shall be deemed given (i) if delivered by first-class
registered or certified mail domestic, three business days after so mailed, (ii) if delivered by nationally recognized overnight carrier, one (1) business day after so mailed,
(iii) if delivered by International Federal Express (or comparable service), two (2) business days after so mailed, (iv) if delivered by facsimile, upon electric confirmation of
receipt and shall be delivered as addressed as follows:



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8.    Changes.This Agreement may not be modified or amended except pursuant to an instrument in writing signed by
the Company and the Investor.

9.    Headings.The headings of the various sections of this Agreement have been inserted for convenience of
reference only and shall not be deemed to be part of this Agreement.

10.    Severability.In case any provision contained in this Agreement should be invalid, illegal or unenforceable
in any respect, the validity, legality and enforceability of the remaining provisions contained herein shall not in any way be affected or impaired thereby.

11.    Governing Law.This Agreement shall be governed by, and construed in accordance with, the internal laws of
the State of Minnesota, without giving effect to the principles of conflicts of law.

12.    Counterparts.This Agreement may be executed in two or more counterparts, each of which shall constitute an
original, but all of which, when taken together, shall constitute but one instrument, and shall become effective when one or more counterparts have been signed by each party hereto and delivered to
the other parties.

13.    Independent Nature of Investors.The obligations of each Investor under any Agreement are several and not
joint with the obligations of any other Investor, and no Investor shall be responsible in any way for the performance of the obligations of any other Investor under any Agreement. The decision of each
Investor to purchase Shares as part of the Offering has been made by such Investor independently of any other Investor. Nothing contained herein, and no action taken by any Investor pursuant hereto,
shall be deemed to constitute the Investors as a partnership, an association, a joint venture or any other kind of entity, or create a presumption that the Investors are in any way acting in concert
or as a group with respect to such obligations or the transactions contemplated by the Offering. Each Investor shall be entitled to independently protect and enforce its rights, including without
limitation the rights arising out of this Agreement.

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EXHIBIT A        Endocardial Solutions, Inc.        STOCK CERTIFICATE QUESTIONNAIRE

Pursuant to Section 4 of the Agreement, please provide us with the following information:

|1. |  | The exact name that your Shares are to be registered in (this is the name that will appear on your stock certificate(s)). You may use a nominee name if appropriate: |  | 
|-- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | 
|   |  |                                                                                                                                                                      |  | 
|2. |  | The relationship between the Investor and the registered holder listed in response to item 1 above:                                                                  |  | 
|   |  |                                                                                                                                                                      |  | 
|3. |  | The mailing address of the registered holder listed in response to item 1 above:                                                                                     |  | 
|   |  |                                                                                                                                                                      |  | 
|4. |  | The Social Security Number or Tax Identification Number of the registered holder listed in the response to item 1 above:                                             |  | 
|   |  |                                                                                                                                                                      |  | 

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EXHIBIT B        Endocardial Solutions, Inc.        INVESTOR QUESTIONNAIRE        (all information will be treated confidentially)

To:
Endocardial Solutions, Inc.,

This
Investor Questionnaire ("Questionnaire") must be completed by each potential investor in connection with the offer and sale of the
shares of the common stock, par value $.01 per share (the "Shares"), of Endocardial Solutions, Inc. (the
"Company"). The Shares are being offered and sold by the Company without registration under the Securities Act of 1933, as amended (the
"Securities Act"), and the securities laws of certain states, in reliance on the exemptions contained in Section 4 of the Securities Act and on
Regulation D promulgated thereunder and in reliance on similar exemptions under applicable state laws. The Company must determine that a potential investor meets certain suitability
requirements before offering or selling Shares to such investor. The purpose of this Questionnaire is to assure the Company that each investor will meet the applicable suitability requirements. The
information supplied by you will be used in determining whether you meet such criteria, and reliance upon the private offering exemption from registration is based in part on the information herein
supplied.

This
Questionnaire does not constitute an offer to sell or a solicitation of an offer to buy any security. Your answers will be kept strictly confidential. However, by signing this
Questionnaire you will be authorizing the Company to provide a completed copy of this Questionnaire to such parties as the Company deems appropriate in order to ensure that the offer and sale of the
Shares will not result in a violation of the Securities Act or the securities laws of any state and that you otherwise satisfy the suitability standards applicable to purchasers of the Shares. All
potential investors must answer all
applicable questions and complete, date and sign this Questionnaire. Please print or type your responses and attach additional sheets of paper if necessary to complete your answers to any item.

A.    BACKGROUND INFORMATION

|Name: | 
|----- | 
|      | 

|Business Address: |                    
|----------------- | -------------------
|                  | (Number and Street)

|      
|------
|(City)

|Telephone Number: (    ) | 
|------------------------ | 
|                         | 

|Residence Address: |                    
|------------------ | -------------------
|                   | (Number and Street)

|      
|------
|(City)

|Telephone Number: (    ) | 
|------------------------ | 
|                         | 

B-1

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If
an individual:

Age:
    Citizenship:
  
  Where registered to vote:

If
a corporation, partnership, limited liability company, trust or other entity:

|Type of entity: | 
|--------------- | 
|                | 

|State of formation: |  |  | Date of formation: | 
|------------------- |  |  | ------------------ | 
|                    |  |  |                    | 

|Social Security or Taxpayer Identification No. | 
|---------------------------------------------- | 
|                                               | 

Send
all correspondence to (check one):  Residence
Address                                       Business Address

B-2

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B.    STATUS AS ACCREDITED INVESTOR

The undersigned is an "accredited investor" as such term is defined in Regulation D under the Securities Act, as at the time of the sale of the Shares the
undersigned falls within one or more of the following categories (Please initial one or more, as applicable):

| |  | (1) |  | a bank as defined in Section 3(a)(2) of the Securities Act, or a savings and loan association or other institution as defined in Section 3(a)(5)(A) of the Securities Act whether acting in its individual or
fiduciary capacity; a broker or dealer registered pursuant to Section 15 of the Securities Exchange Act of 1934; an insurance company as defined in Section 2(13) of the Securities Act; an investment company registered under the Investment
Company Act of 1940 or a business development company as defined in Section 2(a)(48) of that act; a Small Business Investment Company licensed by the U.S. Small Business Administration under Section 301(c) or (d) of the Small Business
Investment Act of 1958; a plan established and maintained by a state, its political subdivisions, or any agency or instrumentality of a state or its political subdivisions for the benefit of its employees, if such plan has total assets in excess of
$5,000,000; an employee benefit plan within the meaning of the Employee Retirement Income Security Act of 1974 if the investment decision is made by a plan fiduciary, as defined in Section 3(21) of such act, which is either a bank, savings and
loan association, insurance company, or registered investment adviser, or if the employee benefit plan has total assets in excess of $5,000,000 or, if a self-directed plan, with the investment decisions made solely by persons that are accredited
investors;(1)
| |  | --- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  | (2) |  | a private business development company as defined in Section 202(a)(22) of the Investment Adviser Act of 1940;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
| |  | (3) |  | an organization described in Section 501(c)(3) of the Internal Revenue Code of 1986, as amended, corporation, Massachusetts or similar business trust, or partnership, not formed for the specific purpose of acquiring the Shares offered, with
total assets in excess of $5,000,000;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
| |  | (4) |  | a natural person whose individual net worth, or joint net worth with that person's spouse, at the time of such person's purchase of the Shares exceeds $1,000,000;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
| |  | (5) |  | a natural person who had an individual income in excess of $200,000 in each of the two most recent years or joint income with that person's spouse in excess of $300,000 in each of those years and has a reasonable expectation of reaching the same
income level in the current year;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
| |  | (6) |  | a trust, with total assets in excess of $5,000,000, not formed for the specific purpose of acquiring the Shares offered, whose purchase is directed by a sophisticated person as described in Rule 506(b)(2)(ii) of Regulation D;
and                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
| |  | (7) |  | an entity in which all of the equity owners are accredited investors (as defined above).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

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C.    REPRESENTATIONS

The undersigned hereby represents and warrants to the Company as follows:

1.Any purchase of the Shares would be solely for the account of the undersigned and not for the account of any other person
or with a view to any resale, fractionalization, division, or distribution thereof.

2.The information contained herein is complete and accurate and may be relied upon by the Company, and the undersigned will
notify the Company immediately of any material change in any of such information occurring prior to the closing, if any, with respect to the purchase of Shares by the undersigned or any
co-purchaser.

3.There are no suits, pending litigation, or claims against the undersigned that could materially affect the net worth of
the undersigned as reported in this Questionnaire.

4.The undersigned acknowledges that there may occasionally be times when the Company, based on the advice of its counsel,
determines that it must suspend the use of the Prospectus forming a part of the Registration Statement (as such terms are defined in the Stock Purchase Agreement to which this Questionnaire is
attached) until such time as an amendment to the Registration Statement has been filed by the Company and declared effective by the Securities and Exchange Commission or until the Company has amended
or supplemented such Prospectus. The undersigned is aware that, in such event, the Shares will not be subject to ready liquidation, and that any Shares purchased by the undersigned would have to be
held during such suspension. The overall commitment of the undersigned to investments which are not readily marketable is not excessive in view of the undersigned's net worth and financial
circumstances, and any purchase of the Shares will not cause such commitment to become excessive. The undersigned is able to bear the economic risk of an investment in the Shares.

5.The undersigned has carefully considered the potential risks relating to the Company and a purchase of the Shares, and
fully understands that the Shares are speculative investments which involve a high degree of risk of loss of the undersigned's entire investment. Among others, the undersigned has carefully considered
each of the risks described under the headings "Cautionary Statements" in the Company's Annual Report on Form 10-K for the year ended December 31, 2001.

6.The following is a list of all states and other jurisdictions in which blue sky or similar clearance will be required in
connection with the undersigned's purchase of the Shares:
.

The
undersigned agrees to notify the Company in writing of any additional states or other jurisdictions in which blue sky or similar clearance will be required in connection with the
undersigned's purchase of the Shares.

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IN
WITNESS WHEREOF, the undersigned has executed this Questionnaire this            day
of                        , 200    , and declares under oath that it is truthful and
correct.

| |  | Print Name
| |  | ----------
| |  | By:       
| |  |           
| |  | Signature 
| |  | Title:    
| |  |           
| |  |           

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EXHIBIT C        Endocardial Solutions, Inc.        CERTIFICATE OF SUBSEQUENT SALE

Wells
Fargo Bank Minnesota, N.A.



Dear
Sir/Madam:

The
undersigned hereby certifies, in connection with the sale of shares of Common Stock of the Company included in the table of Selling Stockholders in the Prospectus, that the
undersigned has sold the Shares pursuant to the Prospectus and in a manner described under the caption "Plan of Distribution" in the Prospectus and that such sale complies with all applicable
securities laws, including, without limitation, the Prospectus delivery requirements of the Securities Act of 1933, as amended.

| | Selling Stockholder (the beneficial owner): | 
| | ------------------------------------------- | 
| |                                             | 

| | Record Holder (e.g., if held in name of nominee): | 
| | ------------------------------------------------- | 
| |                                                   | 

| | Restricted Stock Certificate No.(s): | 
| | ------------------------------------ | 
| |                                      | 

| | Number of Shares Sold: | 
| | ---------------------- | 
| |                        | 

| | Date of Sale: | 
| | ------------- | 
| |               | 

In
the event that you receive a stock certificate(s) representing more shares of Common Stock than have been sold by the undersigned, then you should return to the undersigned a newly
issued certificate for such excess shares in the name of the Record Holder and BEARING A RESTRICTIVE LEGEND. Further, you should place a stop transfer on your records with regard to such certificate.

|Dated: |  |  | Very truly yours,
|------ |  |  | -----------------
|       |  |  |                  
|       |  |  | By:              
|       |  |  |                  
|       |  |  | Print Name:      
|       |  |  |                  
|       |  |  | Title:           
|       |  |  |                  

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EXHIBIT D        FORM OF LEGAL OPINIONJanuary     , 2003

To:
The Investors in Common Stock of Endocardial Solutions, Inc.

Ladies
and Gentlemen:

We
have acted as counsel for Endocardial Solutions, Inc., a Delaware corporation (the "Company"), in connection with the issuance of            shares (the "Shares") of the
Company=s Common Stock, $.01 par value per share, pursuant to those certain Stock Purchase Agreements, dated as
of                        , 200    , including the exhibits thereto (collectively, the
"Agreement"), between the Company and the Investors named therein. This opinion is being delivered to you pursuant to Section 2 of the Agreement. Capitalized terms used herein are as defined in
the Agreement unless otherwise specifically provided herein.

We
have examined such documents and have reviewed such questions of law as we have considered necessary or appropriate for the purpose of this opinion.

In
rendering our opinion below, we have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, and the conformity to authentic
originals of all documents submitted to us as copies. We have also assumed the legal capacity for all purposes relevant hereto of all parties to all relevant agreements other than the Company. As to
questions of fact material to our opinion, we have relied, without independent verification, on the representations and warranties contained in the Agreement and certificates of officers of the
Company and public officials.

Our
opinions expressed below as to certain factual matters are qualified as being limited "to our knowledge" or by other words to the same or similar effect. Such words, as used herein,
mean the information known to Kenneth L. Cutler and Robert A. Kuhns, the attorneys in this firm who have represented the Company in connection with the matters addressed herein. In rendering such
opinions, we have not conducted any independent investigation or consulted with other attorneys in our firm with respect to the matters covered by the Agreement. No inference as to our knowledge with
respect to such matters should be drawn from the fact of our representation of the Company.

Based
on the foregoing, we are of the opinion that:



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The
opinions set forth above are subject to the following qualifications and exceptions:



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The
opinions expressed herein are based on an analysis of existing laws and court decisions and cover certain matters not directly addressed by such authorities. The foregoing opinions
are being furnished to you solely for your benefit in connection with the transactions contemplated by the Agreement and may not be relied upon by any other person without our prior written consent.
We disclaim any obligation to update this opinion letter for events occurring or coming to our attention, or any changes in the law taking effect, after the date hereof.



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