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                THIS DOCUMENT HAS BEEN TRANSLATED INTO ENGLISH.

                                                                   EXHIBIT 10.19

              Real Property Building Sale and Purchase Agreement

The parties to this Building Sale and Purchase Agreement (the "Agreement") are
Buyer, iAsiaWorks, Inc. (hereinafter referred to as B), and Seller, Teng Fu
Construction Co., Ltd. (hereinafter referred to as S).  For the purpose of the
transaction whereby S sells to B all property hereinafter described (the "Real
Property"), the parties have mutually agreed to and hereby set forth the
following provisions in order to facilitate mutual compliance.

Section 1: Identification of the Real Property (in the event of any discrepancy
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in such identification records, the records kept at the applicable government
land office shall prevail)

  [*]. Explanatory information regarding the Building (see Exhibit 2).

Section 2: Explanation of Payments
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  1.  The parties agree that payments shall be made in either cash or sight
      checks upon the following listed payment dates:

  2.  The total purchase price is [*] (the "Total Purchase Price").

  3.  The installment payment due upon the signing of this Agreement shall be
      five percent (5%) of the Total Purchase Price. On the day after the
      signing of this Agreement, B shall pay S the initial payment in the amount
      of [*].

  4.  The second installment payment shall be five percent (5%) of the Total
      Purchase Price, and shall be paid in the amount of [*] within one (1) week
      after the signing of this Agreement.

  5.  The third installment payment shall be five percent (10%) of the Total
      Purchase Price, and shall be paid in the amount of [*] within two (2) days
      after the completion of the curtain wall of the Building.

  6.  The fourth installment payment shall be five percent (5%) of the Total
      Purchase Price, and shall be paid in the amount of [*] within two (2) days
      after the application for the use permit.

  7.  The fifth installment payment shall be five percent (5%) of the Total
      Purchase Price, and shall be paid in the amount of [*] within two (2) days
      after the procurement of the use permit.

  8.  The sixth installment payment shall be seventy percent (70%) of the Total
      Purchase Price, and shall be paid in the amount of [*].

          a.  In the event that B does not take out a loan, twenty (20) days
              after S delivers written notification to B that title to the
              Building can be transferred, the sixth installment payment shall
              be paid to S in either cash or a sight check. At the same time, S
              shall deliver to B all paperwork and documents required for the
              transferal of registration of the Building, but in any event the
              date for such delivery shall be after October 1, 2000. In the

[*] - CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION.  CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.
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              event that title to the Building can be transferred before October
              1, 2000, such date may be moved forward upon the written agreement
              of B.

          b.  In the event that B, or any third party designated by B to hold
              title in such party's name, borrows funds:

                    i.    Within one day following (A) title registration in the
                          name of B or any such third party designated by B and
                          (B) the completion of loan application procedures with
                          the lender bank, such lender bank shall directly pay
                          such amount into the designated bank account of S.

                    ii.   Within twenty (20) days after S delivers written
                          notification to B that title to the Building can be
                          transferred, B shall complete all relevant procedures
                          to apply for a bank loan. In the event that B fails to
                          meet this deadline, it shall be deemed that B will not
                          procure a bank loan. After B pays in full the
                          installment payments listed in Section 2, clauses 3,
                          4, 5, 6 and 7 of this Agreement and delivers to S the
                          "Payment Agreement Letter" executed by the lender
                          bank, S and B shall affix their respective seals on
                          the title transfer certificate.

                    iii.  B hereby agrees that, following the procurement of a
                          collateralized loan with a bank using the Building
                          and the land on which the Building shall be located
                          [*] as collateral, the parties shall apply in a
                          single application for the registration of title
                          transfer for the Building and the land on which the
                          Building shall be located, and the establishment and
                          registration of collateral rights for the bank loan.

Section 3: Construction Schedule
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  1.  S estimates that the curtain wall of the Building will be completed before
      July 15, 2000, and shall make its best efforts to adhere to such estimated
      date.

  2.  S estimates that the use permit will be obtained before September 15,
      2000, and shall make its best efforts to adhere to such estimated date.

  3.  S estimates that it will make physical transfer of the Building before
      October 15, 2000, and shall make its best efforts to adhere to such
      estimated date.

Section 4: Transfer of Title
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  1.  In the event that B does not procure a loan:

          a.   At the time when B makes the sixth installment payment, S shall
               affix its seal to and deliver to B the paperwork and official
               documents required for the registration of the transfer of title
               of the Building. In the event that such official documents are
               incomplete or the procedure is not completed properly, so that
               the need arises for S to affix its seal to or procure additional
               official documents, S shall unconditionally cooperate in all
               respects, and may not take advantage of any such situation by
               rejecting a request for its cooperation or making any demands for
               compensation. Any

[*] - CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.
<PAGE>

               violator of this clause shall be in breach of this Agreement and
               shall be liable to reimburse B for its losses.

          b.   When registration of the transfer of title takes place, the
               registration of such title transfer shall be in the name of B or
               any third party designee of B.

  2.  In the event that B or the third-party registrant designated by B procures
      a bank loan:

          a.   Upon discussion between the parties, they may jointly authorize
               the firm of Land Registration Agent Lin Sheng-Yi (Land Scribe) to
               execute the registration of the Real Property. Related fees shall
               be borne by B.

          b.   The parties shall, within five (5) days following the completion
               by B of the procedures set forth in Section 2, Clauses 3, 4, 5, 6
               and 7, deliver to the Land Registration Agent (Land Scribe) the
               paperwork and official documents required for the registration of
               transfer of title, with their respective seals affixed thereto,
               for execution of the procedures for registration of the
               transferal of rights.

          c.   In the event that, due to the incompleteness of such official
               documents or the improper execution of such procedures, so that
               the need arises for S to affix its seal to or procure additional
               official documents, S shall unconditionally cooperate in all
               respects, and may not take advantage of any such situation by
               rejecting a request for its cooperation or making any demands for
               compensation. Any violator of this clause shall be in breach of
               this Agreement and shall be liable to reimburse B for its losses
               resulting from such violation.

          d.   Upon the execution of title transfer registration, title shall be
               registered in the name of B or such third party registrant that
               is designated by B. In the event that, for any reason
               attributable to B, it is not possible to cooperate with the Land
               Registration Agent (Land Scribe) and procure official documents
               required for the transfer of title, so that the tax payments or
               expenses of S are thereby increased, all such additional expenses
               shall be borne by B, except for the portions of such additional
               payments that are incurred before the delay and shall be payable
               by both parties.

Section 5: Liability for Warrantee of Title and Authorization
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  S hereby warrants that it possesses free and clear title to the Real Property,
  that the Real Property has not been previously sold to other buyers, and that
  that the Real Property does not encroach upon the land of any third parties.
  In the event that a third party alleges any rights or establishes additional
  rights or a lessee relationship, S shall assume responsibility for clearing
  title before B makes the final installment payment so that B may take title
  free and clear of any such claims.  In the event that B incurs any losses as a
  result of such third-party claims, S shall fully compensate B therefor.

Section 6: Assumption of Tax Payments
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  1.  The parties hereby agree that payment of the building tax, utilities and
      other miscellaneous fees shall be borne by S before physical transfer of
      the Building, and shall be borne by B after physical transfer of the
      Building.

  2.  Payment of the registration fee for this transaction, the stamp tax, the
      deed tax (including notarization fees) and witness certification fees
      shall be borne by B. The land value increment tax and construction benefit
      fee shall be borne by S. Neither party may renege on its obligations
      hereunder, but in the event of an increase in the land value increment tax
      resulting from a delay caused by B, B shall bear any resulting additional
      land value increment tax. (Deed tax paid pursuant to this Agreement shall
      be based upon the appraised value of the Building.)

Section 7: Physical Transfer of Building
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  1.  The Building shall be transferred and taken possession of pursuant to a
      punch-list physical inspection. B shall, at the time of transfer of the
      building as notified by S, accept transfer and take possession after an
      on-site inspection.

  2.  Before the punch-list inspection and transfer of the Building, in the
      event of (a) occupation and use of the Building by a third party, (b) a
      natural disaster or major geological change, or (c) other force majeure
      events resulting in damage or destruction, S shall assume responsibility
      for mitigation and restoration, and shall not cause B to bear any loss or
      liability, so that B takes the Building in a state of full completion.

  3.  Before the punch-list inspection and transfer of the Building, S shall
      not, commencing from the execution of this Agreement, without
      authorization take, remove or destroy any interior or exterior fixtures,
      including without limitation doors, windows, kitchen equipment, toilets,
      and public facilities, and shall transfer such fixtures to B in their
      original condition. S shall maintain public facilities and electrical
      equipment in a complete and whole state, and warrant them in accordance
      with the provisions of Section 8 of this Agreement.

  4.  The parties shall arrange a meeting with engineers and relevant personnel
      to account for any change orders in the construction of the Building on an
      item-by-item basis. B shall bear any additional cost, or enjoy any cost
      reduction, due to any increase or decrease in expenses arising from any
      such change order, after all such increases and/or decreases are totaled.

  5.  After B completes the following listed items, S shall cooperate with B to
      allow B to enter the building before physical transfer thereof to fit out
      the interior:

          a.   B shall provide a complete itemized list and detailed drawings
               relating to the fitting out of the Building, and may enter the
               interior to commence fitting out after obtaining the approval of
               S and contractor of S.

          b.   The parties shall execute a "Fitting Out Agreement" setting forth
               that the various construction items are only for the purpose of
               fitting out the premises and not for the purpose of conducting a
               punch-list inspection for acceptance thereof; provided, however,
               that the parties hereby agree that, after the completion of the
               various sale and purchase procedures set forth in this Agreement,
               S shall not again present the Building to B for punch-
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               list inspection and acceptance, and that such punch-list
               inspection and acceptance shall be deemed complete.

          c.   B shall assume liability for any danger within the construction
               area for fitting out works. In the event of any destruction or
               loss to the construction site of S due to fitting out activities
               of B, B shall be liable for compensating S, but S shall assume
               such liability in the event that the construction activities of S
               are the sole cause of such destruction or loss.

          d.   B shall pay [*] per every six (6) square feet as a fitting out
               deposit; provided, however, that such deposit shall not be used
               to defray any construction activities conducted by S.

          e.   B may enter the premises to engage in fitting out activities only
               after obtaining the prior written approval of S.

Section 8: Liability for Breach
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  1.  In the event that either of the parties does not carry out its obligations
      pursuant to this Agreement, and fails to cure such breach within two (2)
      weeks after notification and request for cure from the non-breaching
      party, the non-breaching party may immediately terminate this Agreement.

  2.  Upon the execution of this Agreement, the parties may not renege on this
      Agreement or fail to execute their obligations hereunder; otherwise, such
      breaching party shall be found in breach of this Agreement and shall be
      dealt with accordingly.

  3.  In the event that B breaches this Agreement by refusing to purchase the
      Real Property or acts in any other way so as to breach this Agreement, S
      may, in addition to immediately terminating this Agreement, refuse to
      refund any and all payments made by B up to the time of the applicable
      breach. In the event that B makes any payment more than two (2) weeks
      after such payment is due, B shall pay S a late penalty after the
      expiration of such two-week cure period to be assessed in the amount of
      two hundredths of one percent (0.02%) of the Total Purchase Price per day.
      S may also terminate this Agreement, and may refuse to refund to B any and
      all payments made by B up to the time of such termination; provided,
      however, that in the event that title shall have already been transferred
      to B and the Real Property shall have been transferred to B for B's use, B
      shall unconditionally return the Real Property to S. B shall bear any
      related costs.

  4.  In the event that S refuses to sell in violation of this Agreement, is
      unable to make any payment pursuant hereto, refuses to accept any payment
      made to it pursuant hereto, or commits any other act in breach of this
      Agreement, B may terminate this Agreement. In such event, S hereby agrees
      to immediately refund in full to B all payments made by B pursuant to this
      Agreement, and within five (5) days to return an amount to B equivalent to
      twice the amount of all payments made by B to S up to the time of such
      termination so as to compensate B for any losses due to the breach of this
      Agreement. The parties shall apply at the same time to cancel any title
      transfer that may be in progress at such time, and S shall bear any
      resultant taxes or fees.

[*] - CERTAIN INFORMATION ON THIS PAGE HAS BEEN OMITTED AND FILED SEPARATELY
WITH THE COMMISSION.  CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO
THE OMITTED PORTIONS.
<PAGE>

  5.  In the event that S is unable to (a) complete the curtain wall of the
      Building within forty-five (45) days after the estimated completion date,
      (b) is unable to obtain a use permit within sixty (60) days after the
      estimated date for obtaining such use permit, or (c) is unable to execute
      the physical transfer of the Building within sixty (60) days of the
      estimated date for such physical transfer, each such estimated date being
      set forth in Section 3 of this Agreement, then S shall pay B a late
      penalty after the expiration of such relevant estimated date to be
      assessed in the amount of two hundredths of one percent (0.02%) of the
      Total Purchase Price per day. B may also terminate this Agreement, and
      following such termination S hereby agrees to immediately refund in full
      to B all payments made by B pursuant to this Agreement up to the date of
      such termination, plus interest calculated at an annual rate of eight
      percent (8%).

  6.  This Agreement shall become effective at the same time as the Real
      Property Land Sale and Purchase Agreement, and any failure to carry out
      obligations pursuant to one agreement shall be deemed a breach of both
      agreements.

  7.  S estimates that title to the Building will be transferred to B before
      October 15, 2000. In the event that S is unable to transfer title within
      sixty (60) days following such estimated date, then S shall pay B a late
      penalty after the expiration of such relevant estimated date to be
      assessed in the amount of two hundredths of one percent (0.02%) of the
      Total Purchase Price per day. B may also terminate this Agreement, and
      following such termination S hereby agrees to immediately refund in full
      to B all payments made by B pursuant to this Agreement up to the date of
      such termination, plus interest calculated at an annual rate of eight
      percent (8%).

  8.  In the event that B makes payment pursuant to this Agreement by sending
      wired funds, the date of payment shall be the date when B wires such
      funds, so that B shall be deemed to make payment in accordance with this
      Agreement if the date when such payment is wired is within the date
      specified herein. The date when S receives such wired funds shall not be
      deemed the date of payment of such funds.

Section 9: Warranty
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  1.  S hereby warrants that the Building shall meet quality standards that are
      not lower than those for buildings constructed by S in the Neihu District
      within one (1) year before the execution of this Agreement.

  2.  S hereby warrants the structure of the Building (including the foundation,
      the primary load-bearing beams and rafters, and the floors) for ten years
      from the physical transfer of the Building, and warrants fixtures
      (including doors, windows, elevators, electrical generators, air
      conditioning, fire extinguishers and toilets) for one year after the
      physical transfer of the Building; provided, however, that loss or
      destruction due to natural disaster, geological changes, intentional
      destruction due to human activities, other events for which S cannot
      assume responsibility, and inappropriate use of the Building by B, shall
      be excluded herefrom.

  3.  S hereby warrants that the structure of the Building is not irradiated or
      composed of beach sand, and does not contain any construction materials
      that are harmful to
<PAGE>

      human health or affect the safety of the general public; otherwise, S
      shall be obligated to unconditionally repurchase the Building at the
      original purchase price.

Section 10: In regard to the rights and obligations related to the Building, B
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has already carefully read the Agreement over a period of seven (7) days and
agrees to act in accordance with the provisions of this Agreement.  In the event
that B transfers the rights and obligations pursuant to this Agreement to a
third party, B shall obtain the approval of S; provided, however, that such
approval shall not be required if B is acquired by or merges with a company
possessing comparable financial strength to that of B.

Section 11: Unperformed Works
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In the event that works pursuant to this Agreement are not fully performed, all
such matters shall be resolved in accordance with applicable laws, regulations
and good practices, and in good faith.

Section 12: The exhibits to this Agreement shall have the same effect as this
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Agreement.  This Agreement shall become effective at the same time as the Real
Property Land Sale and Purchase Agreement, and a breach of any part of either
agreement shall be deemed a breach of both agreements.

Section 13: Severability
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The parties have executed this Agreement by signing it and affixing their seals
to it, and neither party shall renege.  This Agreement has been executed in two
copies for the purpose of preventing the parties from relying upon unverifiable
oral understandings.  This Agreement shall be signed and shall have seals
affixed by both parties.  Each party shall hold one copy of this Agreement.
(When the parties contact each other or notify each other of works to be
performed, written notice shall be delivered via registered mail to the parties
at the addresses listed on this Agreement, and in the event that delivery of
such notices is refused or such notices are returned to the sender, then notice
shall be deemed given on the date of attempted delivery.  If either party has a
change of address, such party shall give immediate written notification to the
other party; otherwise the other party may still deliver notice to the address
listed on this Agreement.)

Section 14: Jurisdiction
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All works that are contemplated by this Agreement but that are not fully
performed shall be negotiated and handled in accordance with applicable laws and
regulations, practices, good faith and fair dealing.  In the event of any
dispute giving rise to litigation, the parties hereby agree that jurisdiction
for initial proceedings shall be laid at the local court serving the
jurisdiction encompassing the land upon which the Building is located.

This Agreement is hereby executed by the following parties:
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Buyer (B):     iAsiaWorks, Inc.      /s/ David Holub
               Legal Representative/Responsible Party:   David S. Holub
               Address:             2000 Alameda de las Pulgas, Suite 125
                                    San Mateo, CA 94403 U.S.A.

Seller (S):    Teng Fu Construction Co., Ltd.
               Legal Representative/ /s/Bruce Hsieh
               Responsible Party:   Bruce Hsieh
               Mailing Address:     Ho Hsing Road, Alley 6, No. 10, 3rd Floor
                                    Wen Shan District, Taipei City
               GUI Number:          96951978
               Tel.:                2362-3966

May 17, 2000