Exhibit 10.1


                                                                  EXECUTION COPY



            SERIES A CUMULATIVE CONVERTIBLE PREFERRED STOCK PURCHASE

                                    AGREEMENT

                          Dated as of November 22, 2002

                                      among

                               A.M. CASTLE & CO.,

                           the INVESTORS named herein

                                       and

               W.B. & CO. for itself, and as nominee and agent of

                                 such INVESTORS

<PAGE>


                                TABLE OF CONTENTS
                                -----------------


                                                                            Page
                                                                            ----


ARTICLE I    DEFINITIONS AND INTERPRETATION....................................1
     1.1.   Definitions........................................................1
     1.2.   Interpretation.....................................................4

ARTICLE II   AUTHORIZATION AND SALE OF SERIES A PREFERRED SHARES...............5
     2.1.   Purchase and Sale of Series A Preferred............................5
     2.2.   Delivery of Series A Preferred Shares; Payment of Purchase Price...6

ARTICLE III  COVENANTS.........................................................6
     3.1.   Compliance with Agreements.........................................6
     3.2.   Current Public Information; Listing................................6
     3.3.   Reservation of Common Stock........................................6
     3.4.   Termination........................................................7
     3.5.   Pre-emptive Rights.................................................7
     3.6.   Registration Rights................................................8
     3.7.   Board Representatives..............................................8
     3.8.   Schedule 13D and 13G...............................................8
     3.9.   Use of Proceeds....................................................8

ARTICLE IV   TRANSFER OF RESTRICTED SECURITIES.................................8
     4.1.   General Provisions.................................................8
     4.2.   Rule 144A..........................................................8
     4.3.   Legend.............................................................8
     4.4.   Legend Removal.....................................................9

ARTICLE V    REPRESENTATIONS AND WARRANTIES OF THE COMPANY.....................9
     5.1.   Organization, Qualifications and Corporate Power...................9
     5.2.   Authorization.....................................................10
     5.3.   Authorized Capital Stock..........................................10
     5.4.   No Conflicts......................................................10
     5.5.   SEC Documents; Financial Statements...............................11
     5.6.   Absence of Certain Changes........................................11
     5.7.   Absence of Litigation.............................................11
     5.8.   No Undisclosed Liabilities........................................12
     5.9.   No General Solicitation...........................................12
     5.10.  No Integrated Offering............................................12
     5.11.  Brokers...........................................................12
     5.12.  Absence of Labor Dispute..........................................12
     5.13.  Possession of Intellectual Property...............................12
     5.14.  Possession of Licenses and Permits................................13
     5.15.  Title to Property.................................................13
     5.16.  Compliance with Law...............................................13
     5.17.  Tax Matters.......................................................13
     5.18.  Absence of Further Requirements...................................13

ARTICLE VI   REPRESENTATIONS AND WARRANTIES OF THE INVESTORS..................14
     6.1.   Organization, Qualifications and Corporate Power..................14
     6.2.   Authorization.....................................................14

                                      -i-

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                                TABLE OF CONTENTS
                                -----------------
                                   (continued)



                                                                            Page
                                                                            ----

     6.3.   Brokers...........................................................15
     6.4.   Investment Representations........................................15
     6.5.   Absence of Further Requirements...................................15
     6.6.   The Nominee.......................................................15

ARTICLE VII  MISCELLANEOUS....................................................16
     7.1.   Survival of Representations and Warranties........................16
     7.2.   Amendments and Waivers............................................16
     7.3.   Successors and Assigns............................................16
     7.4.   No Third Party Beneficiaries......................................16
     7.5.   Remedies..........................................................16
     7.6.   Indemnification...................................................16
     7.7.   Severability......................................................17
     7.8.   Notices...........................................................17
     7.9.   Governing Law.....................................................18
     7.10.  Submission to Jurisdiction........................................18
     7.11.  Attorneys' Fees...................................................18
     7.12.  Execution in Counterparts.........................................19
     7.13.  Transaction Expenses..............................................19
     7.14.  Entire Agreement..................................................19
     7.15.  Actions by the Investors..........................................19

                                      -ii-

<PAGE>


EXHIBITS
--------

Exhibit A                  Articles Supplementary
Exhibit B                  Registration Rights Agreement

SCHEDULE
--------

1.1                        List of Investors


                                     -iii-

<PAGE>


       SERIES A CUMULATIVE CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT

          SERIES A CUMULATIVE CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT
(this "Agreement"), dated as of November 22, 2002, among A.M. Castle & Co., a
Maryland corporation (the "Company"), the persons and entities listed on
Schedule 1.1 attached hereto (the "Investors") and W.B. & Co., an Illinois
general partnership, executing this Agreement for itself, and as nominee and
agent of the Investors (the "Nominee").

                                    RECITALS
                                    --------

          WHEREAS, the Company desires to issue and sell to the Investors, and
the Investors desire to purchase from the Company, an aggregate of 12,000 shares
of the authorized and unissued shares of Series A Cumulative Convertible
Preferred Stock, $.01 par value per share, of the Company (the "Series A
Preferred"), which shares of Series A Preferred are convertible into shares of
common stock, $.01 par value per share, of the Company (the "Common Stock").

          NOW, THEREFORE, in consideration of the foregoing and the mutual
representations, warranties, covenants and agreements contained herein, and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the Parties hereby agree as follows:

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION
                         ------------------------------

          1.1. Definitions. For the purposes of this Agreement, the following
terms have the meanings specified or referred to in this Section 1.1:


          "Affiliate" means, with respect to any particular Person, any other
Person that directly or indirectly controls, is controlled by or is under common
control with such particular Person. For the purpose of this definition,
"control" means the possession, directly or indirectly, of the power to direct
the management and policies of a Person, whether through the ownership of voting
securities, by contract or otherwise.

          "Agreement" has the meaning set forth in the first paragraph of this
Agreement.

          "Articles of Incorporation" means the Company's Articles of
Incorporation, as amended by the Articles Supplementary attached hereto as
Exhibit A.

          "Board" means the Board of Directors of the Company.

          "By-laws" means the Company's By-laws, as amended.

          "Common Stock" has the meaning set forth in the Recitals.

<PAGE>


          "Company" has the meaning set forth in the first paragraph of this
Agreement.

          "Conversion Common Shares" means the Common Stock issued or issuable
upon conversion of the Series A Preferred Shares. For purposes of this
Agreement, any Person who holds Series A Preferred Shares shall be deemed to be
the holder of the Conversion Common Shares obtainable upon conversion of the
Series A Preferred Shares, regardless of any restriction or limitation on the
conversion of the Series A Preferred Shares, such Conversion Common Shares shall
be deemed to be in existence, and such Person shall be entitled to exercise the
rights of a holder of Conversion Common Shares hereunder. As to any particular
Conversion Common Shares, such shares shall cease to be Conversion Common Shares
when they have been (x) effectively registered under the Securities Act and
disposed of in accordance with the registration statement covering them, (y)
distributed to the public through a broker, dealer or market maker pursuant to
Rule 144 under the Securities Act (or any similar provision then in force) or
(z) repurchased by the Company.

          "Exchange Act" means the Securities Exchange Act of 1934, as amended,
or any similar federal law then in force.

          "GAAP" means United States generally accepted accounting principles
consistently applied, in effect at the date of the financial statement(s) to
which such term refers.

          "Indemnified Liabilities" has the meaning set forth in Section 7.5.

          "Indemnitees" has the meaning set forth in Section 7.5.

          "Indemnitor" has the meaning set forth in Section 7.5.

          "Investors" has the meaning set forth in the first paragraph of this
Agreement.

          "Lien" means any mortgage, pledge, security interest, encumbrance,
lien, claim or charge of any kind (including any conditional sale or other title
retention agreement or lease in the nature thereof).

          "Material Adverse Effect" means any change or effect that,
individually or in the aggregate with any such other changes or effects, is
materially adverse to the business, properties, assets, liabilities, condition
(financial or otherwise) or results of operations of the Company and its
Subsidiaries, taken as a whole, but shall exclude (i) any change or effect
relating or due to general economic conditions or conditions in the Company's
industry, (ii) any change or effect disclosed in any SEC Document, and (iii) any
change or effect otherwise disclosed to the Investors or the Nominee or their
respective representatives prior to the date hereof.

          "Nominee" has the meaning set forth in the first paragraph of this
Agreement.

          "Offer Period" has the meaning set forth in Section 3.5(a).

          "Offered Securities" has the meaning set forth in Section 3.5(a).

                                      -2-

<PAGE>


          "Party" means the Company and each of the Investors and the Nominee.

          "Permitted Lien" means (i) liens with respect to Taxes not yet due and
payable or which are being contested in good faith by appropriate proceedings,
(ii) mechanics', materialmens' or contractors' liens or encumbrances or any
similar lien or restriction, (iii) easements, rights-of-way, restrictions and
other similar charges and encumbrances not interfering with the ordinary conduct
of the business of the Company, (iv) liens created under the Company's or its
Subsidiaries' borrowing or financing arrangements, (v) purchase money security
interests, (vi) liens arising in connection with sale-leaseback transactions and
(vi) liens existing on the date of this Agreement.

          "Person" means an individual, a partnership, a corporation, a limited
liability company, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization, a governmental entity or any
department, agency or political subdivision thereof or any other entity.

          "Prohibited Action" has the meaning set forth in Section 3.7.

          "Purchase Price" has the meaning set forth in Section 2.2(b).

          "Registration Rights Agreement" means the Registration Rights
Agreement, dated November 22, 2002, among the Company, the Investors and the
Nominee for itself, and as nominee and agent of the Investors, attached hereto
as Exhibit B.

          "Restricted Securities" means (i) the Series A Preferred issued
hereunder and (ii) the Conversion Common Shares. As to any particular Restricted
Securities, such securities shall cease to be Restricted Securities when they
have (a) been effectively registered under the Securities Act and disposed of in
accordance with the registration statement covering them, (b) been distributed
to the public through a broker, dealer or market maker pursuant to Rule 144 (or
any similar provision then in force) under the Securities Act or become eligible
for sale pursuant to Rule 144(k) (or any similar provision then in force) under
the Securities Act, or (c) been otherwise transferred and new certificates for
them not bearing the Securities Act legend set forth in Section 4.3 have been
delivered by the Company in accordance with Section 4.4. Whenever any particular
securities cease to be Restricted Securities, the holder thereof shall be
entitled to receive from the Company, without expense, new securities of like
tenor not bearing a Securities Act legend of the character set forth in Section
4.3. Any holder requesting the removal of such legend shall deliver or cause to
be delivered to the Company a certificate executed by the holder and an opinion
of such holder's counsel, such certificate and opinion to be in form and
substance reasonably satisfactory to the Company.

          "SEC" means the Securities and Exchange Commission and includes any
governmental authority or agency succeeding to the functions thereof.

          "SEC Documents" has the meaning set forth in Section 5.5.

          "Securities Act" means the Securities Act of 1933, as amended, or any
similar federal law then in force.

                                      -3-

<PAGE>


          "Series A Preferred" has the meaning set forth in the Recitals.

          "Series A Preferred Shares" has the meaning set forth in Section 2.1.

          "Subsidiary" means any entity in which the Company, directly or
indirectly, owns a controlling position of capital stock or holds a controlling
position of an equity or similar interest.

          "Tax" (and, with correlative meaning, "Taxes" and "Taxable") means:

          (i) any federal, state, local or foreign net income, gross income,
     gross receipts, windfall profit, severance, property, production, sales,
     use, license, excise, franchise, employment, payroll, withholding,
     alternative or add-on minimum, ad valorem, value-added, transfer, stamp, or
     environmental tax, or any other tax, custom, duty, governmental fee or
     other like assessment or charge of any kind whatsoever, together with any
     interest or penalty, addition to tax or additional amount imposed by any
     governmental authority; and

          (ii) any liability of the Company for the payment of amounts with
     respect to payments of a type described in clause (i) as a result of any
     obligation of the Company under any Tax sharing or indemnity arrangement.

          "Transaction Documents" means the agreements, documents and
instruments expressly contemplated hereby and thereby, including the
Registration Rights Agreement.

          1.2. Interpretation. (a) As used in this Agreement and each
Transaction Document, unless the context clearly indicates otherwise:

          (i)   words used in the singular include the plural and words in the
     plural include the singular;

          (ii)  reference to any Person includes such Person's successors and
     assigns, but only if such successors and assigns are permitted by this
     Agreement or such other Transaction Document, and reference to a Person in
     a particular capacity excludes such Person in any other capacity;

          (iii) reference to any gender includes the other gender;

          (iv)  whenever the words "include," "includes" or "including" are used
     in this Agreement or any Transaction Document, they shall be deemed to be
     followed by the words "without limitation" or "but not limited to" or words
     of similar import;

          (v)   reference to any Article, Section, Exhibit or schedule means
     such Article or Section of, or such Exhibit or schedule to, this Agreement,
     as the case may be, and references in any Section or definition to any
     clause means such clause of such Section or definition;

                                      -4-

<PAGE>


          (vi)   the words "herein," "hereunder," "hereof," "hereto" and words
     of similar import shall be deemed references to this Agreement as a whole
     and not to any particular Section or other provision hereof;

          (vii)  reference to any agreement, instrument or other document means
     such agreement, instrument or other document as amended, supplemented and
     modified from time to time to the extent permitted by the provisions
     thereof and by this Agreement;

          (viii) reference to any law (including statutes and ordinances) means
     such law (including all rules and regulations promulgated thereunder) as
     amended, modified, codified or reenacted, in whole or in part, and in
     effect at the time of determining compliance or applicability, and
     reference to any particular provision of any law shall be interpreted to
     include any revision of or successor to that provision regardless of how
     numbered or classified;

          (ix)   relative to the determination of any period of time, "from"
     means "from and including," "to" means "to but excluding" and "through"
     means "through and including";

          (x)    in the event of any conflict between the provisions of the body
     of this Agreement and the Exhibits or schedules hereto, the provisions of
     the body of this Agreement shall control; and

          (xi)   the titles to Articles and headings of Sections contained in
     this Agreement have been inserted for convenience of reference only and
     shall not be deemed to be a part of or to affect the meaning or
     interpretation of this Agreement.

          (b) This Agreement and each of the Transaction Documents were
negotiated by the Parties with the benefit of legal representation, and no rule
of construction or interpretation otherwise requiring this Agreement or any of
the Transaction Documents to be construed or interpreted against any Party shall
apply to any construction or interpretation hereof. Subject to Section 7.7, this
Agreement shall be interpreted and construed to the maximum extent possible so
as to uphold the enforceability of each of the terms and provisions hereof, it
being understood and acknowledged that this Agreement was entered into by the
Parties after substantial negotiations and with full awareness by the Parties of
the terms and provisions hereof and the consequences thereof.

                                   ARTICLE II

               AUTHORIZATION AND SALE OF SERIES A PREFERRED SHARES
               ---------------------------------------------------

          2.1. Purchase and Sale of Series A Preferred. Simultaneously upon the
execution of this Agreement, and in reliance upon the representations and
warranties of the Company set forth herein or in any certificate or other
document delivered pursuant hereto, the Company shall issue, sell and deliver to
the Nominee, on behalf of the Investors, and the Investors shall purchase from
the Company at a purchase price of $1,000.00 per share, 12,000 shares of Series
A Preferred (the "Series A Preferred Shares") having the rights and preferences
set forth in the Articles Supplementary attached hereto as Exhibit A.

                                      -5-

<PAGE>


          2.2. Delivery of Series A Preferred Shares; Payment of Purchase Price.
(a)Simultaneously upon the execution of this Agreement, the Company shall issue
and deliver to the Nominee, on behalf of the Investors, one or more stock
certificates, duly executed by the Company and registered in the Company's stock
ledger in the Nominee's name, evidencing the Series A Preferred Shares.

          (b) Simultaneously upon the execution of this Agreement, as payment in
full for the Series A Preferred Shares being purchased by it under this
Agreement, and against delivery of the stock certificate(s) therefor as
described in subparagraph (a) above, the Investors shall transfer to the account
of the Company by wire transfer $12 million (the "Purchase Price").

                                   ARTICLE III

                                    COVENANTS
                                    ---------

          3.1. Compliance with Agreements. The Company shall perform and observe
all of its obligations to each holder of the Series A Preferred Shares and all
of its obligations to each holder of the Conversion Common Shares set forth in
the Articles of Incorporation and the By-laws.

          3.2. Current Public Information; Listing. (a) Any information to be
furnished to or on behalf of any Investor or the Nominee (or any assignee or
successor of any Investor or transferee of the Series A Preferred Shares) in
connection with the transactions contemplated by this Agreement shall only be
furnished pursuant to the terms of a confidentiality agreement, in form and
substance reasonably acceptable to the Company, executed by the Investors and
the Nominee and any other recipient of such information prior to the receipt of
such information.

          (b) The Company shall file all reports required to be filed by it
under the Securities Act and the Exchange Act and the rules and regulations
adopted by the SEC thereunder and, subject to Section 3.2(a), shall take such
further action as the Investors may reasonably request, which request shall be
made through the Nominee, all to the extent required to enable the Investors to
sell Restricted Securities pursuant to Rule 144 adopted by the SEC under the
Securities Act (as such rule may be amended from time to time) or any similar
rule or regulation hereafter adopted by the SEC. The Company will file with the
American Stock Exchange and the Chicago Stock Exchange, if required, the
appropriate notification form for the listing of additional shares under the
rules and regulations of such exchange (and otherwise in a form reasonably
acceptable to the Nominee) in respect of the Conversion Common Shares and the
Company shall use its commercially reasonable efforts to cause the Conversion
Common Shares to at all times be listed (or traded) on one of the New York Stock
Exchange, American Stock Exchange, Chicago Stock Exchange or NASDAQ System.

          3.3. Reservation of Common Stock. The Company shall at all times
reserve and keep available out of its authorized but unissued shares of Common
Stock, solely for the purpose of issuance upon the conversion of the Series A
Preferred Shares, such number of shares of Common Stock issuable upon the
conversion of all outstanding Series A Preferred Shares.

                                      -6-

<PAGE>


          3.4. Termination. Notwithstanding any other provision of this Article
III, upon such time as the Investors no longer own any Series A Preferred
Shares, the Company's obligations pursuant to this Article III shall terminate
(provided that the Company shall remain liable for any breach thereof prior to
such termination).

          3.5. Pre-emptive Rights. (a) Except for Excluded Issuances (as defined
below in Section 3.5(d)), if the Company authorizes or issues any of its Common
Stock, Series A Preferred or other equity securities, debt securities containing
equity features or other securities or other rights convertible into or
containing options or rights to acquire any such debt or equity securities
("Offered Securities"), the Company shall first offer, by written notice (a
"Proposal Notice"), to sell to each holder of Series A Preferred Shares, a
portion of such Offered Securities equal to the product of (i) the number of
such Offered Securities and (ii) the quotient determined by dividing (A) the
number of Conversion Common Shares held by such holder by (B) the number of
shares of Common Stock then outstanding (calculated assuming the conversion into
Common Stock of all Series A Preferred Shares immediately prior to such proposed
issuance). The Proposal Notice shall be delivered to each holder of Series A
Preferred Shares at least 20 days prior to the proposed issuance and shall set
forth in reasonable detail the Offered Securities, the purchase price thereof,
the payment terms and such holder's percentage allotment. During such 10 day
period following delivery of the Proposal Notice (the "Offer Period"), each
holder of Series A Preferred Shares shall be entitled to purchase his portion of
such Offered Securities at the most favorable price and on the most favorable
terms as such Offered Securities are to be offered to any other Person.

          (b) In order to exercise its purchase rights hereunder, each holder of
Series A Preferred Shares must deliver a written notice to the Company
describing its election hereunder within 10 days after receipt of the Proposal
Notice from the Company; provided that any such election may be subject to the
consummation of the sale of the Offered Securities and other rights described in
the Proposal Notice on the terms set forth therein.

          (c) To the extent any of the Offered Securities are not acquired by
any holder of Series A Preferred Shares pursuant to Section 3.5(a), the Company
shall be entitled to sell such Offered Securities on terms and conditions no
more favorable to the purchasers thereof than those offered to the holders of
Series A Preferred Shares during the 90 days following the expiration of the
Offer Period. Any Offered Securities so offered or sold by the Company to any
Person after such 90-day period must be reoffered to each holder of Series A
Preferred Shares pursuant to the terms of Section 3.5(a).

          (d) For purposes of the foregoing, "Excluded Issuances" means (A)
issuances to employees, officers, directors and consultants of the Company of
stock options or restricted stock under any equity incentive or restricted stock
plan or plans currently existing or approved hereafter by the Board, (B) the
issuance of shares of Common Stock upon exercise of the options referred to in
clause (A) of this subsection in accordance with their terms, (C) issuances of
Common Stock or other equity securities of the Company upon conversion or
exchange of any Series A Preferred Shares or of any securities issued directly
or indirectly upon conversion or exchange thereof, in each case in accordance
with the Articles of Incorporation, (D) the issuance of 17,397 shares of Common

                                      -7-

<PAGE>


Stock to William Blair & Company, LLC in connection with the transactions
contemplated hereby and (E) any other issuance of Common Stock or other Company
securities if and to the extent that the Investors holding a majority of the
outstanding Series A Preferred Shares have waived in writing the provisions of
this Section 3.5 in respect thereof.

          3.6. Registration Rights. Simultaneously upon the execution of this
Agreement, the Company and the Nominee, for itself, and as nominee and agent of
the Investors, shall have entered into the Registration Rights Agreement
attached hereto as Exhibit B.

          3.7. Board Representatives. Until the fifth anniversary of the date of
this Agreement, and so long as the Board includes two representatives of the
Investors (which such representatives are Michael Simpson and Patrick Herbert as
of the date of this Agreement), the Investors shall not take any action alone or
in concert with others to directly or indirectly seek to elect or control a
majority of the Board (a "Prohibited Action"). Notwithstanding the preceding
sentence, before the Investors at any time initiate or commence any Prohibited
Action, they shall cause all of their representatives on the Board to resign
from the Board.

          3.8. Schedule 13D and 13G. The Nominee and each of the Investors agree
to provide the Company with a copy of any Schedule 13D or 13G that the Nominee
or any Investor intends to file with the SEC in connection with its purchase of
Series A Preferred Shares in advance of such filing and such 13D or 13G shall be
true and correct when filed with the SEC.

          3.9. Use of Proceeds. The Company shall use the proceeds from the sale
of the Series A Preferred Shares for general working capital purposes, including
the repayment of debt.

                                   ARTICLE IV

                        TRANSFER OF RESTRICTED SECURITIES
                        ---------------------------------

          4.1. General Provisions. Restricted Securities are transferable only
pursuant to (a) public offerings registered under the Securities Act, (b) Rule
144 or Rule 144A of the SEC (or any similar rule or rules then in force) if such
rule is available and (c) any other legally available means of transfer.

          4.2. Rule 144A. Subject to Section 3.2(a), upon the request of
Nominee, on behalf of any Investor, the Company shall promptly supply to the
Nominee all information regarding the Company required to be delivered in
connection with a transfer pursuant to Rule 144A of the SEC.

          4.3. Legend. Each certificate or instrument representing Restricted
Securities shall be imprinted with a legend in substantially the following form:

     "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
     REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. THE
     TRANSFER OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE IS

                                      -8-

<PAGE>


     SUBJECT TO THE CONDITIONS SPECIFIED IN THE SERIES A CUMULATIVE
     CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT, DATED AS OF
     NOVEMBER 22, 2002, AND MODIFIED FROM TIME TO TIME, AMONG A.M.
     CASTLE & CO. (THE "COMPANY"), THE INVESTORS NAMED THEREIN (THE
     "INVESTORS") AND W.B. & CO. FOR ITSELF, AND AS NOMINEE AND AGENT
     OF THE INVESTORS AND THE COMPANY RESERVES THE RIGHT TO REFUSE THE
     TRANSFER OF SUCH SECURITIES UNTIL SUCH CONDITIONS HAVE BEEN
     FULFILLED WITH RESPECT TO SUCH TRANSFER. A COPY OF SUCH
     CONDITIONS SHALL BE FURNISHED BY THE COMPANY TO THE HOLDER HEREOF
     UPON WRITTEN REQUEST AND WITHOUT CHARGE."

          4.4. Legend Removal. If any Restricted Securities become eligible for
sale pursuant to Rule 144(k), the Company shall, upon the request of the holder
of such Restricted Securities, remove the legend set forth in Section 4.3 from
the certificates for such Restricted Securities. Any holder requesting the
removal of such legend shall deliver or cause to be delivered to the Company a
certificate executed by the holder and an opinion of such holder's counsel, such
certificate and opinion to be in form and substance reasonably satisfactory to
the Company.

                                   ARTICLE V

                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY
                  ---------------------------------------------

          As an inducement to the Investors to enter into this Agreement and to
purchase the Series A Preferred Shares, the Company hereby represents and
warrants to the Investors and agrees as follows:

          5.1. Organization, Qualifications and Corporate Power. (a) The Company
is a corporation duly incorporated, validly existing and in good standing under
the laws of the State of Maryland. The Company is duly qualified to do business
as a foreign corporation and is in good standing in each jurisdiction where such
qualification is necessary, except in those jurisdictions where failure to be so
qualified or in good standing would not, individually or in the aggregate, have
a Material Adverse Effect. The Company has full corporate power and authority to
own or lease and to operate and use its properties and assets and to carry on
its business as currently conducted.

          (b) The Company has full corporate power and authority (i) to execute,
deliver and perform each of the Transaction Documents, (ii) to issue, sell and
deliver the Series A Preferred Shares and the Conversion Common Shares and (iii)
to carry out fully and perform its obligations under the terms hereof and
thereof.

          (c) Each of the Subsidiaries is a corporation or limited liability
company duly incorporated or formed, as the case may be, validly existing and in
good standing under the laws of its jurisdiction of incorporation or formation,
as the case may be. Each of the Subsidiaries is duly qualified to do business as

                                      -9-

<PAGE>


a foreign corporation and is in good standing in each jurisdiction where such
qualification is necessary, except in those jurisdictions where failure to be so
qualified or in good standing would not, individually or in the aggregate, have
a Material Adverse Effect. Each of the Subsidiaries has full corporate power and
authority to own or lease and to operate and use its properties and assets and
to carry on its business as currently conducted.

          5.2. Authorization. The execution, delivery and performance of this
Agreement and each of the Transaction Documents, and the issuance, sale and
delivery of the Series A Preferred Shares and the Conversion Common Shares, have
been duly authorized and approved by all requisite action on the part of the
Company, its directors and its shareholders. This Agreement has been duly
authorized, executed and delivered by the Company and is the legal, valid and
binding obligation of the Company enforceable in accordance with its terms, and
each of the Transaction Documents to which the Company is a party has been duly
authorized by the Company and, upon execution and delivery by the Company, will
be a legal, valid and binding obligation of the Company enforceable in
accordance with its respective terms, except in each case (i) to the extent that
bankruptcy, insolvency, reorganization, moratorium, fraudulent transfer or other
similar laws of general applicability relating to or affecting the enforcement
of creditors' rights and by the effect of general principles of equity
(regardless of whether enforceability is considered in a proceeding in equity or
at law) and (ii) the rights to indemnity may be limited by federal and state
securities laws and public policy considerations.

          5.3. Authorized Capital Stock. (a) The authorized capital stock of the
Company consists of (i) 30,000,000 shares of Common Stock, of which 15,098,770
shares are issued and outstanding as of the date hereof, and of which 2,004,703
have been reserved for issuance upon exercise of granted stock options; and (ii)
10,000,000 shares of preferred stock, $.01 par value per share, of which 12,000
shares have been designated as Series A Preferred, no shares of which are issued
and outstanding. The Company has reserved for issuance sufficient shares of
Common Stock for issuance upon conversion of all outstanding Series A Preferred
Shares.

          (b) The Series A Preferred Shares, when issued, sold and delivered in
accordance with the terms of this Agreement and the Articles of Incorporation,
will be duly and validly issued, fully paid, non-assessable and free and clear
of all Liens, except any Liens created by or through any Investor.

          (c) The Conversion Common Shares issuable upon conversion of the
Series A Preferred Shares will, when issued, in accordance with the conversion
provisions of the Series A Preferred Shares, be duly and validly issued, fully
paid, non-assessable and free and clear of all Liens, except any Liens created
by or through any Investor.

          5.4. No Conflicts. Neither the execution and delivery of this
Agreement or any other Transaction Document or the consummation of any of the
transactions contemplated hereby or thereby nor compliance with or fulfillment
of the terms, conditions and provisions hereof or thereof will conflict with,
result in a breach of the terms, conditions or provisions of, or constitute a
default, an event of default or an event creating rights of acceleration,
termination or cancellation or a loss of rights under, or result in the creation
or imposition of any, Lien (other than Permitted Liens) upon any of the assets

                                      -10-

<PAGE>


or properties of the Company, under (1) the Articles of Incorporation or
By-laws, (2) any note, instrument, agreement, mortgage, lease, license,
franchise, permit or other authorization, right, restriction or obligation to
which the Company or any of its Subsidiaries is a party or any of their
respective assets or properties is subject or by which the Company or any of its
Subsidiaries is bound, (3) any court order, judgement, decree or order to which
the Company or any of its Subsidiaries is a party or any of their respective
assets or properties is subject or by which the Company or any of its
Subsidiaries is bound, or (4) any law, ordinance or regulation affecting the
Company, any of its Subsidiaries or any of their respective assets or
properties, other than, in the case of clauses (2), (3) and (4), any such
conflicts, breaches, defaults, rights or Liens (other than Permitted Liens)
that, individually or in the aggregate, would not have a Material Adverse
Effect, or would not prevent the consummation of any of the transactions
contemplated hereby. The Company has not granted any pre-emptive rights or other
similar rights which would provide any Person the right to acquire any shares of
Series A Preferred as of the date hereof.

5.5. SEC Documents; Financial Statements. Since January 1, 2001, the Company has
filed all reports, schedules, forms, statements and other documents required to
be filed by it with the SEC pursuant to the reporting requirements of the
Exchange Act (all of the foregoing filed prior to the date hereof and all
exhibits included therein and financial statements and schedules thereto and
documents incorporated by reference therein being hereinafter referred to as the
"SEC Documents"). As of their respective dates (or in the case of any amended
SEC Document, as of the date of amendment), each SEC Document complied in all
material respects with the requirements of the Exchange Act and the rules and
regulations of the SEC promulgated thereunder applicable to such SEC Document,
and none of the SEC Documents, at the time they were filed with the SEC (or in
the case of any amended SEC Document, as of the date of amendment), contained
any untrue statement of a material fact or omitted to state a material fact
required to be stated therein or necessary in order to make the statements
therein, in light of the circumstances under which they were made, not
misleading. As of their respective dates, the consolidated financial statements
of the Company included in the SEC Documents complied as to form in all material
respects with applicable accounting requirements and the published rules and
regulations of the SEC with respect thereto. Such consolidated financial
statements have been prepared in accordance with generally accepted accounting
principles, consistently applied, during the periods involved (except (i) as may
be otherwise indicated in such consolidated financial statements or the notes
thereto, or (ii) in the case of unaudited interim statements, to the extent they
may exclude footnotes or may be condensed or summary statements) and fairly
present in all material respects the consolidated financial position of the
Company as of the dates thereof and the consolidated results of its operations
and consolidated cash flows for the periods then ended (subject, in the case of
unaudited statements, to normal year-end audit adjustments). As of the date
hereof, the Company is not aware of any unresolved comments issued by the SEC
with respect to the SEC Documents.

          5.6. Absence of Certain Changes. Since the most recent filing by the
Company with the SEC, except as set forth in any SEC Document, there has been no
event or change that, individually or in the aggregate, whether or not arising
in the ordinary course of business, would have a Material Adverse Effect.

          5.7. Absence of Litigation. Except as set forth in the SEC Documents,
there is no action, suit, proceeding, inquiry or investigation before or by any
court, public board, government agency, self-regulatory organization or body

                                      -11-

<PAGE>


pending or, to the knowledge of the Company, threatened against or affecting the
Company or any of its Subsidiaries, which, if adversely determined, would,
individually or in the aggregate, have a Material Adverse Effect.

          5.8. No Undisclosed Liabilities. There are no liabilities of the
Company or any of its Subsidiaries, other than (i) as disclosed in the SEC
Documents, (ii) liabilities incurred since September 30, 2002 in the ordinary
course of business, (iii) liabilities under this Agreement and any other
Transaction Document or incurred in connection with the transactions
contemplated hereby or thereby and (iv) liabilities which would not,
individually or in the aggregate, have a Material Adverse Effect.

          5.9. No General Solicitation. Neither the Company, nor any of its
Affiliates, nor any Person acting on its or their behalf, has engaged in any
form of general solicitation or general advertising (within the meaning of
Regulation D under the 1933 Act) in connection with the offer or sale of the
Series A Preferred.

          5.10. No Integrated Offering. Neither the Company, nor any of its
Affiliates, nor any Person acting on its or their behalf has, directly or
indirectly, made any offers or sales of any security or solicited any offers to
buy any security, under circumstances that would require registration of any of
the Series A Preferred under the Securities Act or cause this offering of the
Series A Preferred to be integrated with prior offerings by the Company for
purposes of the Securities Act.

          5.11. Brokers. The Company has no agreement with any broker, finder or
similar agent with respect to the transactions contemplated by this Agreement
for which the Company shall have any liability or responsibility, except for
consideration owed to William Blair & Company, which the Company hereby
expressly covenants and agrees to pay in full.

          5.12. Absence of Labor Dispute. No labor dispute with the employees of
the Company or any of its Subsidiaries exists or, to the knowledge of the
Company, is threatened, which, in either case, individually or in the aggregate,
would result in a Material Adverse Effect.

          5.13. Possession of Intellectual Property. The Company and its
Subsidiaries own or have the right to use the intellectual property used to
carry on the business as currently operated by them, except to the extent the
failure to so own or have such right would not result in a Material Adverse
Effect (the "Intellectual Property"), and neither the Company nor any of its
Subsidiaries has received any notice or is otherwise aware of any infringement
of or conflict with asserted rights of others with respect to any Intellectual
Property or of any facts or circumstances which would render any Intellectual
Property invalid or inadequate to protect the interest of the Company or any of
its Subsidiaries therein, and which infringement or conflict (if the subject of
any unfavorable decision, ruling or finding) or invalidity or inadequacy,
individually or in the aggregate, would result in a Material Adverse Effect. To
the knowledge of the Company, the conduct of the Company's and each of its
Subsidiaries' business has not infringed, misappropriated or conflicted with any
intellectual property of other Persons, except as would not have a Material
Adverse Effect.

                                      -12-

<PAGE>


          5.14. Possession of Licenses and Permits. To the knowledge of the
Company, the Company and its Subsidiaries possess such permits, licenses,
approvals, consents, franchises, grants, easements, variances, exceptions,
certificate and other authorizations issued by the appropriate governmental
entity necessary to own, lease and operate their respective properties and to
conduct their business as currently conducted, except such permits, licenses,
approvals, consents, franchises, grants, easements, variances, exceptions,
certificates and other authorizations the failure of which to possess would not,
individually or in the aggregate, result in a Material Adverse Effect
(collectively, "Governmental Licenses"); to the knowledge of the Company, the
Company and its Subsidiaries are in compliance with the terms and conditions of
all such Governmental Licenses, except where the failure so to comply would not,
individually or in the aggregate, result in a Material Adverse Effect; to the
knowledge of the Company, all of the Governmental Licenses are valid and in full
force and effect, except when the invalidity of such Governmental Licenses or
the failure of such Governmental Licenses to be in full force and effect would
not have a Material Adverse Effect; and neither the Company nor any of its
Subsidiaries has received any notice of proceedings relating to the revocation,
suspension, cancellation or modification of any such Governmental Licenses
which, individually or in the aggregate, if the subject of an unfavorable
decision, ruling or finding, would result in a Material Adverse Effect.

          5.15. Title to Property. The Company and its Subsidiaries have good
and marketable title to all real property owned by the Company and its
Subsidiaries and good title to all other properties owned by them, in each case,
free and clear of all Liens of any kind except (i) Permitted Liens or (ii) Liens
that would not have a Material Adverse Effect. The Company and its Subsidiaries
own, or have a valid leasehold interest in, all material assets necessary for
the conduct of their business as now conducted and presently proposed to be
conducted, except such as would not, individually or in the aggregate, have a
Material Adverse Effect.

          5.16. Compliance with Law. The Company and its Subsidiaries are in
compliance with all applicable laws, except where the failure to be in such
compliance would not (either individually or in the aggregate) have a Material
Adverse Effect. To the knowledge of the Company, neither the Company, any
Subsidiary nor any of their respective officer, directors, representatives or
Affiliates (other than any Investor or any of its Affiliates), has at any time
made any unlawful payments on behalf of the Company for political contributions
or made any bribes, kickback payments or other illegal payments.

          5.17. Tax Matters. All material Tax returns of the Company and each of
its Subsidiaries required by law to be filed have been duly filed and all Taxes
which are due and payable, have been paid, except any such Taxes (i) (x) the
payment of which the Company or any of its Subsidiaries is contesting in good
faith, (y) for which adequate reserves (as determined in accordance with GAAP)
have been provided on the books of the Company or its Subsidiaries involved, and
(z) as to which no Lien other than a Permitted Lien has attached and no
foreclosure, distraint, sale or similar proceedings have been commenced, (ii)
which may result from audits not yet conducted or (iii) the failure of which to
pay would not have a Material Adverse Effect. The charges, accruals and reserves
on the books of the Company and its Subsidiaries in respect of Taxes have been
determined in accordance with GAAP.

          5.18. Absence of Further Requirements. Other than filings with the
Secretary of State of Maryland, the SEC or otherwise with respect to federal or
state securities law, no filing with, or authorization, approval, consent,

                                      -13-

<PAGE>


license, order, registration, qualification or decree of, any governmental
entity, other than those that have been made or obtained, is necessary or
required for the performance by the Company of its obligations under the
Transaction Documents or the consummation by the Company of the transactions
contemplated by the Transaction Documents.

                                   ARTICLE VI

                 REPRESENTATIONS AND WARRANTIES OF THE INVESTORS
                 -----------------------------------------------

          As an inducement to the Company to enter into this Agreement and to
issue and sell the Series A Preferred Shares, each Investor hereby severally
represents and warrants to the Company and agrees with respect to himself or
itself as follows:

          6.1. Organization, Qualifications and Corporate Power. (a) Each
Investor that is a corporation is duly incorporated, validly existing and in
good standing under the laws of the jurisdiction of its incorporation and has
full corporate power and authority to own or lease and to operate and use its
properties and assets and to carry on its business as currently conducted.

          (b) Each Investor that is a trust is validly created and existing
under the laws of the jurisdiction of its creation.

          (c) Each Investor has full individual, trust or corporate, as
applicable, capacity, power and authority (i) to execute, deliver and perform
each of the Transaction Documents, (ii) to purchase and take possession of the
Series A Preferred Shares it is purchasing hereunder and the related Conversion
Common Shares and (iii) to carry out fully and perform its obligations under the
terms hereof and thereof.

          6.2. Authorization. The execution, delivery and performance of this
Agreement and each of the Transaction Documents have been duly authorized and
approved by each Investor. This Agreement has been duly executed and delivered
by or on behalf of each Investor and is the legal, valid and binding obligation
of each Investor enforceable in accordance with its terms, and each of the
Transaction Documents to which such Investor is a party has been duly authorized
by such Investor and, upon execution and delivery by or on behalf of such
Investor, will be a legal, valid and binding obligation of such Investor
enforceable in accordance with its respective terms, except in each case (i) to
the extent that bankruptcy, insolvency, reorganization, moratorium, fraudulent
transfer or other similar laws of general applicability relating to or affecting
the enforcement of creditors' rights and by the effect of general principles of
equity (regardless of whether enforceability is considered in a proceeding in
equity or at law) and (ii) the rights to indemnity may be limited by federal and
state securities laws and public policy considerations.

                                      -14-

<PAGE>


          6.3. Brokers. Neither the Nominee nor any Investor has any agreement
with any broker, finder or similar agent with respect to the transactions
contemplated by this Agreement for which the Nominee or such Investor shall have
any liability or responsibility.

          6.4. Investment Representations. (a) The Series A Preferred Shares
acquired by each Investor pursuant to this Agreement are being acquired for its
own account and without a view to the resale or distribution of such shares or
any Conversion Common Shares or any interest therein other than in a transaction
exempt from registration under the Securities Act.

          (b) Each Investor listed under the heading "Accredited Investor" on
Schedule 1.1 attached hereto is an "accredited investor" as such term is defined
in Rule 501(a) of Regulation D under the Securities Act. Each other Investor has
been advised regarding an investment in the Series A Preferred by a "purchaser
representative" as such term is defined in Rule 501(e) of Regulation D under the
Securities Act.

          (c) Each Investor understands that the Restricted Securities being
sold hereby have not been registered under the Securities Act, or applicable
state securities laws, and are being issued in reliance on exemptions for
private offerings contained in Section 4(2) of the Securities Act and in
reliance on exemptions from the registration requirements of certain state
securities laws. Because the Restricted Securities have not been registered
under the Securities Act or applicable state securities laws, the Restricted
Securities may not be re-offered or resold except through a valid and effective
registration statement or pursuant to a valid exemption from the registration
requirements under the Securities Act and applicable state securities laws.

          (d) Each Investor has sufficient knowledge and experience in financial
and business matters so as to be capable of evaluating the merits and risks of
its investment in the Series A Preferred Shares and is capable of bearing the
economic risks of such investment, including a complete loss of its investment
in the Series A Preferred. Each Investor understands that its investment in the
Series A Preferred involves a high degree of risk.

          (e) Each Investor has been furnished with and carefully read a copy of
the Company's Annual Report on Form 10-K for the year ended December 31, 2001,
each of the Company's Quarterly Reports on Form 10-Q for 2002 and this Agreement
and has been given the opportunity to ask questions of, and receive answers
from, the Company concerning the terms and conditions of the Series A Preferred
and other related matters. The Company has made available to each Investor or
its agents all documents and information relating to an investment in the Series
A Preferred requested by or on behalf of such Investor.

          6.5. Absence of Further Requirements. Other than filings with the
Secretary of State of Maryland, the SEC or otherwise with respect to federal or
state securities law, no filing with, or authorization, approval, consent,

                                      -15-

<PAGE>


license, order, registration, qualification or decree of, any governmental
entity, other than those that have been made or obtained, is necessary or
required for the performance by each Investor of its obligations under the
Transaction Documents or the consummation by each Investor of the transactions
contemplated by the Transaction Documents.

          6.6. The Nominee. The Nominee is an Illinois general partnership and
is the nominee holder of the Series A Preferred Shares for all of the Investors.
The two general partners of the Nominee are Patrick J. Herbert, III and Simpson
Estates, Inc., each of whom share the power to vote the Investors' Series A
Preferred. Except as set forth in the first two sentences of this Section 6.6,
elsewhere in this Agreement and the Transaction Documents, no Investor has any
agreements, arrangements or understandings with any other Person (other than
Affiliates of such Investor) with regard to acquiring, holding, voting or
disposing of any securities of the Company.

                                   ARTICLE VII

                                  MISCELLANEOUS
                                  -------------

          7.1. Survival of Representations and Warranties. All representations
and warranties contained herein or made in writing by any Party in connection
herewith shall survive until the first anniversary of the date of this
Agreement.

          7.2. Amendments and Waivers. Except as otherwise expressly provided
herein, the provisions of this Agreement may be amended, modified or waived if
the Company shall have obtained the written consent of a majority of the holders
of the outstanding Series A Preferred Shares.

          7.3. Successors and Assigns. Except as otherwise expressly provided
herein, all covenants and agreements contained in this Agreement by or on behalf
of any of the Parties will bind and inure to the benefit of the respective
successors and permitted assigns of the Parties, whether so expressed or not.

          7.4. No Third Party Beneficiaries. This Agreement is intended for the
benefit of the Parties hereto and their respective permitted successors and
assigns, and is not for the benefit of, nor may any provision hereof be enforced
by, any other Person.

          7.5. Remedies. Each holder of any Series A Preferred Share or
Conversion Common Share shall have all rights and remedies set forth in this
Agreement, the Articles of Incorporation and any other agreement or contract
that grants rights and remedies to such holders, and all rights that such
holders have under any law. Any Person having any rights under any provision of
this Agreement shall be entitled to enforce such rights specifically, to recover
damages by reason of any breach of any provision of this Agreement and to
exercise all other rights granted by law.

          7.6. Indemnification. Each of the Company and the Investors (jointly
and severally) (for purposes of this Section, an "Indemnitor") shall defend,
protect, indemnify and hold harmless the Investors or the Company, as the case
may be, and all of such Party's partners, officers, directors, employees and
agents (including those retained in connection with the transactions
contemplated by this Agreement), as applicable (collectively, the
"Indemnitees"), from and against any and all actions, causes of action, suits,
claims, losses, costs, penalties, fees, liabilities and damages, and expenses
(irrespective of whether any such Indemnitee is a party to the action for which
indemnification hereunder is sought), and including reasonable attorney's fees
and disbursements (the "Indemnified Liabilities"), incurred by the Indemnitees
as a result of, or arising out of, or relating to any breach by such Indemnitor

                                      -16-

<PAGE>


of any of the representations, warranties or covenants contained in this
Agreement or any of the Transaction Documents for so long as such
representations and warranties or covenants shall survive as contemplated herein
and therein. It is understood that the Indemnitor shall not, in connection with
any proceeding or related proceedings in the same jurisdiction, be liable for
reasonable fees and expenses of more than one separate firm (in addition to
local counsel) for all Indemnitees. To the extent that the foregoing undertaking
may be unenforceable for any reason, the Indemnitor shall make the maximum
contribution to the payment and satisfaction of each of the Indemnified
Liabilities that is permissible under applicable law. Neither the Investors, on
the one hand, nor the Company, on the other hand, shall have any liability for
any inaccuracy in or breach of any representation or warranty by the other if
the Company or the Investors, as the case may be, or any of their or its
officers, employees, counsel or other representatives (including, in the case of
the Investors, the Nominee or any partner in the Nominee or any of their
respective officers, counsel or representatives) had actual knowledge on or
before the date hereof of any fact which would cause it to believe that such
representation or warranty was inaccurate or breached.

          7.7. Severability. Wherever possible, each provision of this Agreement
will be interpreted in such manner as to be effective and valid under applicable
law and in such a way as to, as closely as possible, achieve the intended
economic effect of such provision and this Agreement as a whole, but if any
provision contained herein is, for any reason, held to be invalid, illegal or
unenforceable in any respect, such provision shall be ineffective to the extent,
but only to the extent, of such invalidity, illegality or unenforceability
without invalidating the remainder of such provision or any other provisions
hereof, unless such a construction would be unreasonable.

          7.8. Notices. All notices or other communications required or
permitted hereunder shall be in writing and shall be deemed given or delivered
(a) when delivered personally, (b) if transmitted by facsimile when confirmation
of transmission is received, (c) if sent by registered or certified mail,
postage prepaid, return receipt requested, three business days after mailing or
(d) if sent by reputable overnight courier service, one business day after
delivery to such service; and shall be addressed as follows:

          If to the Company, to

               A.M. Castle & Co.
               3400 North Wolf Road
               Franklin Park, IL  60131
               Attention:  President
               Facsimile:  (847) 455-6930

          with a copy to:

               A.M. Castle & Co.
               3400 North Wolf Road
               Franklin Park, IL  60131
               Attention:  Counsel
               Facsimile:  (847) 455-6930

                                      -17-

<PAGE>


               and

               Sidley Austin Brown & Wood
               Bank One Plaza
               10 South Dearborn Street
               Chicago, Illinois  60603
               Attention:  Thomas A. Cole
                              Kevin F. Blatchford
               Facsimile:  (312) 853-7036

          If to the Investors or the Nominee, to:

               Simpson Estates, Inc.
               30 North LaSalle Street
               Suite 1231
               Chicago, IL  60601
               Attention:  Patrick J. Herbert, III
               Facsimile:  (312) 726-3143

          with a copy to:

               McDermott, Will & Emery
               227 West Monroe Street
               Suite 5500
               Chicago, Illinois  60606
               Attention:  Timothy R.M. Bryant
               Facsimile:  (312) 984-3669

          7.9. Governing Law. This Agreement and the exhibits hereto shall be
governed by, and construed in accordance with, the laws of the State of
Illinois, without giving effect to any choice of law or conflict of law rules or
provisions (whether of the State of Illinois or any other jurisdiction) that
would cause the application of the laws of any jurisdiction other than the State
of Illinois. In furtherance of the foregoing, the internal law of the State of
Illinois shall control the interpretation and construction of this Agreement
(and all exhibits hereto), even though under that jurisdiction's choice of law
or conflict of law analysis, the substantive law of some other jurisdiction
would ordinarily apply.

          7.10. Submission to Jurisdiction. Each of the Parties hereby
irrevocably submits in any suit, action or proceeding arising out of or related
to this Agreement or any of the Transaction Documents, or any of the
transactions contemplated hereby or thereby, to the exclusive jurisdiction of
the United States District Court for the Northern District of Illinois and the
Circuit Court of Cook County, Illinois, and, to the extent permissible by law,
waives any and all claims and objections that any such court is an inconvenient
forum or improper venue.

          7.11. Attorneys' Fees. In the event of any action or suit based upon
or arising out of any actual or alleged breach by any Party of any
representation, warranty or agreement in this Agreement, the prevailing party

                                      -18-

<PAGE>


shall be entitled to recover its reasonable attorneys' fees and expenses
(determined on an aggregate basis with respect to the Investors) of such action
or suit from the losing party, in addition to any other relief ordered by the
court.

          7.12. Execution in Counterparts. This Agreement may be executed in any
number of counterparts, each of which will be considered an original instrument,
but all of which together will be considered one and the same agreement, and
will become binding when one or more counterparts have been signed by and
delivered to each of the Parties.

          7.13. Transaction Expenses. The Company shall pay all costs and
expenses that it incurs, and the reasonable fees and expenses of McDermott, Will
& Emery, special legal counsel to the Investors and the Nominee incurred, in
connection with the negotiation, execution, delivery and performance of this
Agreement and the transactions contemplated hereby.

          7.14. Entire Agreement. This Agreement and the exhibits referred to
herein, the Transaction Documents and the other documents delivered pursuant
hereto contain the entire understanding of the Parties with regard to the
subject matter contained herein or therein, and supersede all prior agreements,
understandings or letters of intent between or among any of the Parties,
including the Term Sheet dated October 24, 2002 entered into by and among the
Company and the Nominee.

          7.15. Actions by the Investors. (a) Each Investor hereby constitutes
and appoints the Nominee, the true and lawful attorney and agent of such
Investor to execute in the name, place and stead of such Investor any and all
amendments to this Agreement and any Transaction Document and all notices,
communications or other instruments necessary or advisable in connection
herewith or therewith; the Nominee to have the full power and authority to do
and perform in the name and on behalf of each Investor every act whatsoever
necessary or advisable to be done on the premises as fully and to all intents
and purposes as such Investor might or could do in person.

          (b) For all purposes of this Agreement and any Transaction Document,
the Investors represent, warrant and covenant that any notice, communication or
action taken by the Nominee may be unconditionally relied upon by the Company as
being for and on behalf of all of the Investors.





                            [SIGNATURE PAGE FOLLOWS]


                                      -19-

<PAGE>


          Agreement IN WITNESS WHEREOF, the Parties have caused this Agreement
to be executed the day and year first above written by its duly authorized
officer or agent.



                                            A.M. CASTLE & CO.



                                            By:  /s/  G. Thomas McKane
                                               --------------------------------
                                            Name:     G. Thomas McKane
                                            Title:    President and CEO


                                            W.B. & CO. for itself, and as
                                            nominee and agent of the Investors
                                            listed on Schedule 1.1 attached
                                            hereto



                                            By:  /s/  Patrick J. Herbert, III
                                               --------------------------------
                                            Name:     Patrick J. Herbert, III
                                            Title:    General Partner



                                            /s/  Patrick J. Herbert, III
                                            -----------------------------------
                                                 Patrick J. Herbert, III, as
                                            Attorney-in-Fact, Trustee or
                                            Authorized Officer for those
                                            Investors listed on Schedule 1.1
                                            attached hereto under the heading
                                            "Patrick J. Herbert, III,
                                            Attorney-in-Fact, Trustee or
                                            Authorized Officer"


                                            United States Trust Company of New
                                            York, as Trustee for those Investors
                                            listed on Schedule 1.1 attached
                                            hereto under the heading "United
                                            States Trust Company of New York,
                                            Trustee"



                                            By:  /s/  Scott A. Salisbury
                                               --------------------------------
                                            Name:     Scott A. Salisbury
                                            Title:    Senior Vice President




                                 Signature Page
                                     to the
            Series A Cumulative Convertible Preferred Stock Purchase