Macquarie Infrastructure Company Trust

Macquarie Infrastructure Company LLC

9,000,000 shares of Trust Stock

Each Representing One Beneficial Interest
in
Macquarie Infrastructure Company Trust

PURCHASE AGREEMENT

October 24, 2006

MERRILL LYNCH & CO.

Merrill Lynch, Pierce, Fenner & Smith

     Incorporated

4 World Financial Center
New York, New York 10080

Citigroup Global Markets Inc.
388 Greenwich Street
New York, New York 10013

Credit Suisse Securities (USA) LLC
Eleven Madison Avenue
New York, New York 10010

as Representatives of the several Underwriters named on Schedule A hereto

Ladies and Gentlemen:

     Macquarie Infrastructure Company LLC, a Delaware limited liability company (the Company), for itself and as sponsor of Macquarie Infrastructure Company Trust, a statutory trust formed under the laws of the State of Delaware (the Trust) confirms its agreement with Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated (Merrill Lynch) and each of the other Underwriters named in Schedule A hereto (collectively, the Underwriters, which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for whom Merrill Lynch, Citigroup Global Markets Inc. (Citigroup) and Credit Suisse Securities (USA) LLC (Credit Suisse) are acting as representatives (in such capacity, the Representatives), with respect to the issue by the Trust, the sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective numbers of shares of trust stock set forth in said Schedule A, each representing one beneficial interest in the Trust (the Trust Stock), and with respect to the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in Section 2(b) hereof to purchase all or any part of 1,350,000 additional shares of Trust Stock to cover overallotments, if any. The aforesaid 9,000,000 shares of Trust Stock (the Initial Securities) to be purchased by the Underwriters and all or any part of the 1,350,000 shares of Trust Stock subject to the option described in Section 2(b) hereof (the Option Securities) are hereinafter called, collectively, the Securities.

     Immediately prior to the delivery of the Initial Securities and the Option Securities, if any, to the Underwriters, the Company, as Sponsor of the Trust, will cause the Trust to sell to the Company the Initial Securities and the Option Securities, if any, in exchange for an equal number of limited liability company interests of the Company as consideration for such limited liability company interests. The aforesaid 9,000,000 limited liability company interests of the Company (the Initial Interests) to be purchased by the Trust and all or any part of the 1,350,000 limited liability company interests of the Company to be sold to the Trust in connection with the option described in Section 2(b) hereof (the Option Interests) are hereinafter called, collectively, the Interests.

     The Trust and the Company understand that the Underwriters propose to make a public offering of the Securities as soon as the Representatives deem advisable after this Agreement has been executed and delivered.

     The Trust and the Company have filed with the Securities and Exchange Commission (the Commission) on October 16, 2006, an automatic shelf registration statement on Form S-3 (Nos. 333-138010, 333-138010-01), including the related base prospectus (the Base Prospectus), which registration statement became effective upon filing under Rule 462(e) of the rules and regulations of the Commission (the 1933 Act Regulations) under the Securities Act of 1933, as amended (the 1933 Act). Such registration statement covers the registration of the Securities under the 1933 Act. Promptly after execution and delivery of this Agreement, the Trust and the Company will prepare and file a final prospectus supplement in accordance with the provisions of Rule 430B (Rule 430B) of the 1933 Act Regulations and paragraph (b) of Rule 424 (Rule 424(b)) of the 1933 Act Regulations. Any information included in such final prospectus supplement that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as Rule 430B Information. Each preliminary prospectus supplement to the Base Prospectus used in connection with the offering of the Securities that was used prior to the filing of the Prospectus (as defined below), together with the Base Prospectus, is herein called a preliminary prospectus. Such registration statement, at any given time, including the amendments thereto at such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act at such time and the documents otherwise deemed to be a part thereof or included therein by 1933 Act Regulations, is herein called the Registration Statement. The Registration Statement at the time it originally became effective is herein called the Original Registration Statement. The final prospectus supplement, together with the Base Prospectus, in the form first furnished to the Underwriters for use in connection with the offering of the Securities, including the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act at the time of the execution of this Agreement, is herein called the Prospectus. For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (EDGAR).

     All references in this Agreement to financial statements and schedules and other information which is contained, included or stated in the Registration Statement, any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by 1933 Act Regulations to be a part of or included in the Registration Statement, any preliminary prospectus or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement, any preliminary prospectus or the Prospectus shall be deemed to mean and include the filing of any document under the Securities Exchange Act of 1934 (the 1934 Act) which is incorporated by reference in the Registration Statement, such preliminary prospectus or the Prospectus, as the case may be.