EXHIBIT p.

                    CALAMOS CONVERTIBLE AND HIGH INCOME FUND

                             Subscription Agreement

      This Agreement made May 16, 2003 by and between Calamos Convertible and
High Income Fund, a Delaware statutory trust (the "Fund"), and Calamos Asset
Management, Inc., an Illinois corporation (the "Subscriber");

                                   WITNESSETH:

      WHEREAS, the Fund has been formed for the purposes of carrying on business
as a closed-end diversified management investment company;

      WHEREAS, the Subscriber has been selected by the Fund's Board of Trustees
to serve as investment adviser to the Fund; and

      WHEREAS, the Subscriber wishes to subscribe for and purchase, and the Fund
wishes to sell to the Subscriber, 7,000 common shares for a purchase price of
$14.325 per share.

      NOW THEREFORE, IT IS AGREED:

      1. The Subscriber subscribes for and agrees to purchase from the Fund
13,450.507 common shares for a purchase price of $14.325 per share. Subscriber
agrees to make payment for these shares at such time as demand for payment may
be made by an officer of the Fund.

      2. The Fund agrees to issue and sell said shares to Subscriber promptly
upon its receipt of the purchase price.

      3. To induce the Fund to accept its subscription and issue the shares
subscribed for, the Subscriber represents that it is informed as follows:

            (a) That the shares being subscribed for have not been and will not
      be registered under the Securities Act of 1933 ("Securities Act");

            (b) That the shares will be sold by the Fund in reliance on an
      exemption from the registration requirements of the Securities Act;

            (c) That the Fund's reliance upon an exemption from the registration
      requirements of the Securities Act is predicated in part on the
      representation and agreements contained in this Subscription Agreement;

            (d) That when issued, the shares will be "restricted securities" as
      defined in paragraph (a)(3) of Rule 144 of the General Rules and
      Regulations under the Securities Act ("Rule 144") and cannot be sold or
      transferred by Subscriber unless they are subsequently registered under
      the Securities Act or unless an exemption from such registration is
      available; and

            (e) That there do not appear to be any exemptions from the
      registration provisions of the Securities Act available to the Subscriber
      for resale for the shares. In the future, certain exemptions may possibly
      become available, including an exemption for limited sales including an
      exemption for limited sales in accordance with the conditions of Rule 144.

The Subscriber understands that a primary purpose of the information
acknowledged in subparagraphs (a) through (e) above is to put it on notice as to
restrictions on the transferability of the shares.

      4. To further induce the Fund to accept its subscription and issue the
shares subscribed for, the Subscriber:

            (a) Represents and warrants that the shares subscribed for are being
      and will be acquired for investment for its own account and not on behalf
      of any other person or persons and not with a view to, or for sale in
      connection with, any public distribution thereof;

            (b) Agrees that any certificates representing the shares subscribed
      for may bear a legend substantially in the following form:

            The shares represented by this certificate have been acquired for
      investment and have not been registered under the Securities Act of 1933
      or any other federal or state securities law. These shares may not be
      offered for sale, sold or otherwise transferred unless registered under
      said securities laws or unless some exemption from registration is
      available.

            (c) Consents, as the sole holder of the Trust's common shares of
      beneficial interest and pursuant to Section 23(b)(2) of the Investment
      Company Act of 1940, to the issuance by the Trust of common shares of
      beneficial interest at a price per share as set forth in the Purchase
      Agreement relating to the public offering of Shares; and

      5. This Subscription Agreement and all of its provisions shall be binding
upon the legal representatives, heirs, successors and assigns of the parties
hereto. This Subscription Agreement may be signed in one or more counterparts,
each of which shall be deemed to be an original.

                                       2

      IN WITNESS WHEREOF, this Subscription Agreement has been executed by the
parties hereto as of the day and date first above written.



                        CALAMOS CONVERTIBLE AND HIGH INCOME FUND



                        By: /s/ James S. Hamman
                           -------------------------------------



                        CALAMOS ASSET MANAGEMENT, INC.


                        By: /s/ Patrick Dudasik
                           -------------------------------------