Document:

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                                                                   Exhibit 10.18

English Translation

CONFIDENTIAL TREATMENT REQUESTED BY GMARKET INC.
CONFIDENTIAL PORTIONS OF THIS DOCUMENT HAVE BEEN REDACTED AND FILED SEPARATELY
WITH THE SECURITIES AND EXCHANGE COMMISSION.

                         ONLINE ADVERTISEMENT AGREEMENT

                                 BY AND BETWEEN

                      GMARKET INC. AND BEST BUYER CO., LTD.

This Online Advertisement Agreement (this "Agreement") is entered by and between
Gmarket Inc. ("Gmarket") and Best Buyer Co., Ltd. ("Best Buyer") as follows:

ARTICLE 1 (PURPOSE)

Gmarket hereby agrees to appoint Best Buyer as its advertisement medium for the
online advertisement of Gmarket, and Best Buyer hereby accepts the appointment
and undertakes to fulfill its duties as Gmarket's advertisement medium in good
faith. The purpose of this Agreement is to provide for rights and obligations
between the parties.

ARTICLE 2 (RIGHTS AND OBLIGATIONS)

1)   Best Buyer shall expose a banner that links to the Internet site of Gmarket
     (http://www.gmarket.co.kr) on its Internet site (http://www.bb.co.kr) for
     the period of two months from January 11, 2006 to March 10, 2006.

2)   Gmarket shall pay Best Buyer the sum of KRW [****] (exclusive of VAT) per
     month in consideration of the exposure of the banner advertisement.

3)   Best Buyer shall issue and deliver to Gmarket invoice on the date set forth
     below in respect of the advertisement fee of KRW [****] (exclusive of VAT):

     -    Issuance date of invoice for the advertisement fee for the first
          month: January 19, 2006

     -    Issuance date of invoice for the advertisement fee for the second
          month: February 19, 2006

[****] = MATERIAL OMITTED: CONFIDENTIAL TREATMENT HAS BEEN REQUESTED AND FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

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4)   On the date set forth below, Gmarket shall pay in cash the amount set forth
     in the invoice issued as above:

     -    Payment date for the advertisement fee for the first month: February
          15, 2006

     -    Payment date for the advertisement fee for the second month: March 15,
          2006

5)   However, if any of the foregoing issuance or payment dates falls on any
     holiday, such issuance or payment shall be made on the immediately
     preceding or following day upon the mutual agreement of the parties.

ARTICLE 3 (EXPOSURE AND PRODUCTION OF ADVERTISEMENT)

1)   Gmarket shall produce the advertisement to be exposed on Best Buyer's site
     ("Advertisement").

2)   The size and the exposure screen of the Advertisement shall be based on the
     advertisement proposal made by Gmarket.

3)   The method of exposing the Advertisement shall be in principle determined
     in accordance with a separate agreement between the parties.

ARTICLE 4 (MUTUAL CONSULTATION)

1)   This Agreement may only be amended by a written agreement of the parties.

2)   Matters not provided for in this Agreement shall be resolved in accordance
     with the relevant laws and commercial practices. Provided, however, matters
     not provided herein shall be, if necessary, separately determined upon
     mutual agreement of the parties, and such separate agreement shall have the
     same effect as that of this Agreement.

ARTICLE 5 (CONFIDENTIALITY)

Neither Gmarket nor Best Buyer may provide to a third party or use for purposes
other than those contemplated under this Agreement the other party's trade
secrets obtained in the course of execution of this Agreement without prior
written consent by the other party, even after the end of the term of this
Agreement, and in the event of breach of the foregoing, the disclosing party
shall be responsible to compensate the other party for damage incurred
therefrom.

ARTICLE 6 (TERMINATION AND COMPENSATION FOR DAMAGE)

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In case that either party breaches its obligations under this Agreement, the
other party may demand correction of the breaches by giving a written notice of
such breach and then if the breaching party fails to correct such breach within
7 days from the date of such written notice, the non-breaching party may
terminate this Agreement.

ARTICLE 7 (PROHIBITION ON TRANSFER)

Neither Gmarket nor Best Buyer may transfer or provide as security its rights
and obligations under this Agreement without a prior written consent of the
other party.

ARTICLE 8 (DISPUTE SETTLEMENT)

Any dispute arising between the parties in connection with this Agreement shall
be brought before the Seoul District Court for resolution.

Both parties have confirmed and then agreed to each of the provisions hereunder.

IN WITNESSETH WHEREOF, both parties have executed two copies of this Agreement
and affixed with their names and seals, each of which shall be kept by the
respective parties.

                                                                January 19, 2006

Gmarket Inc.
Business Registration Number: 220-81-83676
Address: 6th Fl., Nam Seoul Bldg., 1304-3 Seocho-Dong, Seocho-Gu, Seoul
Name: Young Bae Ku (seal)
Title: Representative Director

Best Buyer Co., Ltd.
Business Registration Number: 120-81-95042
Address: 12th Fl, Daebong Bldg., 720-4 Yoksam-Dong, Kangnam-Gu, Seoul
Name: Yong Soo Kim (seal)
Title: Representative Director

                                       3<PAGE>

                                                                   Exhibit 10.19

English Translation

CONFIDENTIAL TREATMENT REQUESTED BY GMARKET INC.
CONFIDENTIAL PORTIONS OF THIS DOCUMENT HAVE BEEN REDACTED AND
FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                        SHOPPING AGENT SERVICE AGREEMENT

ARTICLE 1 (PURPOSE)

The purpose of this Shopping Agent Service Agreement ("Agreement") is to provide
for the method, process and the terms and conditions of the shopping agent
service of Interpark Goodsdaq ("Interpark Goodsdaq") and Best Buyer Co., Ltd.
("Best Buyer").

ARTICLE 2 (DEFINITION)

1.   The Shopping Agent Service ("Service") shall mean the service provided by
     Best Buyer by which users of Best Buyer's site may purchase the products
     sold at the Internet shopping mall operated by Interpark Goodsdaq
     (Goodsdaq: http://www.goodsdaq.com/).

2.   "Sales Commission" shall mean an amount payable by Interpark Goodsdaq to
     Best Buyer with respect to the Service provided by Best Buyer.

3.   "Sales" shall mean the sales of Interpark Goodsdaq generated through the
     Service provided by Best Buyer.

ARTICLE 3 (SCOPE OF COOPERATION)

The parties shall actively cooperate with each other in the following fields in
order to obtain best results through mutual business cooperation:

1.   Provision of information relating to the operation of the shopping mall and
     sales products;

2.   Recording of the sales and cooperation results through the Service; and

3.   Cooperation in joint marketing or in any other fields to improve the effect
     of the Service.

ARTICLE 4 (CONTENTS AND PROVISION OF SERVICE)

1.   Interpark Goodsdaq and Best Buyer shall determine the products and contents
     of the menu to be provided for the Service by mutual agreement, and Best
     Buyer shall provide the Service to Interpark Goodsdaq by creating a link to
     such products and menu contents.

2.   Best Buyer shall provide e-commerce service by which the products can be
     ordered and sold via the Internet shopping mall operated by Interpark
     Goodsdaq.

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ARTICLE 5 (EFFECTIVE DATE AND TERM)

This Agreement shall be effective for one year from the date hereof and shall be
automatically extended for one year unless either party expresses an intention
in writing to modify the terms and conditions hereunder or to terminate this
Agreement by one month prior to expiration of the agreement.

ARTICLE 6 (DETERMINATION AND PAYMENT SERVICE FEE)

1.   The fee for the Service ("Service Fee") shall be paid in a fixed amount per
     month, and the Service Fee shall be as follows:

<TABLE>
<CAPTION>
                              Amount             Issuance Date of Invoice              Payment Date
                       -------------------   -------------------------------   ---------------------------
<S>                    <C>                   <C>                               <C>
Monthly fixed Amount   [****] of the Sales   The 25th day of the immediately   Until the 30th day of the
                                             following month                   immediately following month
VAT
</TABLE>

2.   If any of the issuance or payment dates set forth in Paragraph (1) above
     falls on any holiday, such issuance or payment shall be made on the
     immediately following day.

ARTICLE 7 (SUSPENSION OF PROVISION OF THE SERVICE)

Best Buyer may suspend the Service in any of the following cases:

1.   If the equipment for the Service needs to be repaired;

2.   If the telecommunications business operator as set forth in the
     Telecommunications Business Act ceases to provide telecommunications
     services; or

3.   Under Article 12 hereof.

ARTICLE 8 (TERMINATION)

In any of the following cases, either party shall terminate this Agreement by
giving written notice (including e-mail) to the other party:

1.   If one party breaches or fails to perform any provision of this Agreement;

2.   If one party causes damages to the other party result from gross negligence
     or deliberate action;

3.   If either Interpark Goodsdaq or Best Buyer cannot continue this Agreement
     due to material reasons such as bankruptcy; or

4.   If this Agreement cannot be performed.

[****] = MATERIAL OMITTED: CONFIDENTIAL TREATMENT HAS BEEN REQUESTED AND FILED
     SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

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ARTICLE 9 (PROHIBITION ON TRANSFER)

Neither Interpark Goodsdaq nor Best Buyer may transfer its rights and
obligations under this Agreement without prior written consent of the other
party.

ARTICLE 10 (INTELLECTUAL PROPERTY)

The ownership, copyright and license of the system (hardware and software) and
all design, specifications, materials, technologies, know-how, patents and
utility models related to, or incorporated in, the system which are developed
while performing this Agreement or relating to the performance of this Agreement
(collectively "Intellectual Property") shall belong to the developing party. The
ownership, copyright and license of any Intellectual Property jointly developed
by the parties shall belong to both, Interpark Goodsdaq and Best Buyer.

ARTICLE 11 (CONFIDENTIALITY)

Neither Interpark Goodsdaq nor Best Buyer may disclose to a third party or use
for purposes other than those contemplated under this Agreement the other
party's trade secrets obtained in the course of execution of this Agreement,
without prior written consent by the other party, even after the end of the term
of this Agreement. In the event of breach of the foregoing, the disclosing party
shall be responsible to the other party for damages incurred therefrom.

ARTICLE 12 (FORCE MAJEURE)

Neither party shall be responsible for any delay or default of its obligations
caused directly or indirectly by a force majeure or any event beyond the control
of the either party.

ARTICLE 13 (DISPUTE SETTLEMENT)

Any dispute arising between the parties in connection with this Agreement shall
be brought before the Seoul District Court for resolution.

Both parties have confirmed and agreed to each of the provisions hereunder.

IN WITNESSETH WHEREOF, both parties have executed two copies of this Agreement
and affixed with their names and seals, each of which shall be kept by the
respective parties.

                                                                 October 1, 2003

<TABLE>
<S>                                          <C>
Interpark Goodsdaq:                          Best Buyer:
Name: Young Bae Ku (seal)                    Name: Yong Soo Kim (seal)
Title: Representative Director               Title: Representative Director
</TABLE>

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<TABLE>
<S>                                          <C>
Company Name: Interpark Goodsdaq             Company Name: Best Buyer Co., Ltd.
Business Registration Number: 220-81-83676   Business Registration Number: 120-81-95042
Address: Hyosung Bldg., 44-24 Yoido-Dong,    Address: 6th Fl, Jaesung Bldg., 1487-4
Youngdeungpo-Gu, Seoul                       Seocho-3 Dong, Seocho-Gu, Seoul
</TABLE>

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