Exhibit 99.1

WAIVER NO. 3

          THIS WAIVER NO. 3 is being executed and delivered as of March 30, 2006, by and among Chicago Bridge and Iron Company N.V., a corporation organized under the laws of the Kingdom of the Netherlands (the “Company”), certain Subsidiaries party thereto as Borrowers (the “Subsidiary Borrowers”), JPMorgan Chase Bank, N.A. (successor by merger to Bank One, NA) as Administrative Agent (the “Administrative Agent”) under the hereinafter identified and defined Credit Agreement and the lenders party to said Credit Agreement. All capitalized terms used herein without definition shall have the same meanings as set forth in the Credit Agreement.

WITNESSETH:

          WHEREAS, the Company, the Subsidiary Borrowers, the Lenders and the Administrative Agent are currently party to that certain Amended and Restated Credit Agreement dated as of May 12, 2005 (as the same may be amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”);

          WHEREAS, the Borrowers have requested the Lenders and the Administrative Agent to waive certain provisions of the Credit Agreement in certain respects;

          WHEREAS, the Lenders and the Agent have agreed to waive certain provisions of the Credit Agreement on the terms and conditions set forth in Section 1 hereof.

          NOW, THEREFORE, in consideration of the foregoing premises, the terms and conditions stated herein and other valuable consideration, the receipt and sufficiency of which are hereby acknowledged by the Borrowers and the Lenders, such parties hereby agree as follows:

          1. Waiver. The Borrowers have informed the Lenders that Defaults or Unmatured Defaults have occurred and are continuing, or are about to occur, under Sections 7.1(A)(i)(a), 7.1(A)(ii), 7.1(A)(iii), 7.1(A)(iv), 8.1(B) and 8.1(C) of the Credit Agreement as a result of the Company’s failure to timely (a) file with the Commission its financial results and related documents for the third and fourth quarters of its 2005 fiscal year, for its 2005 fiscal year and for the first quarter of its 2006 fiscal year and (b) deliver to the Administrative Agent and the Lenders the financial reports (including without limitation the plan and forecast) and related documents required under the Credit Agreement for or during such periods (collectively, the “Specified Defaults”). In accordance with the provisions of Section 9.2(i) of the Credit Agreement, the Borrowers have requested that, subject to the terms hereof, the Required Lenders waive the Specified Defaults and waive the application of the default rate of interest provided under Section 2.10 of the Credit Agreement. The Required Lenders hereby agree to such limited waiver and furthermore agree that, solely during the period commencing on November 14, 2005 and ending at the end of the Waiver Period (as defined below) and notwithstanding anything contained in Sections 2.1(A), 2.2(A), 3.2, 3.4, 3.5(A) and other applicable Sections of the Credit Agreement to the contrary, (x) Section 5.3(B) of the Credit Agreement shall not be deemed to

apply to the representations and warranties contained in Sections 6.4 and 6.10 of the Credit Agreement insofar as such Sections relate to the Company’s internally prepared financial statements (and related statements, reports, certificates and documents) for its four fiscal quarter period ending December 31, 2005 which are being delivered to the Lenders in connection with this Waiver (the “Unaudited Statements”) and the financial information (and related statements, reports, certificates and documents) which the Company has delivered to the Lenders on or prior to December 31, 2005 and which the Company is currently in the process of investigating as disclosed to the Lenders, (y) the last sentence of Section 5.3 of the Credit Agreement shall not be applicable and (z) the Company and the Administrative Agent may agree to such modifications to the forms (as set forth in the applicable Exhibits to the Credit Agreement) of Borrowing/Election Notice, request for the issuance of a Letter of Credit and compliance certificate as are reasonably deemed appropriate by the Company and the Administrative Agent to give effect to the foregoing clauses (x) and (y); provided that this waiver shall (i) only remain in effect during the period (the “Waiver Period”) commencing on the date hereof and expiring on the earlier of (a) the occurrence of any Default or Unmatured Default other than one of the Specified Defaults and (b) May 31, 2006 and (ii) be subject to the receipt by the Administrative Agent of evidence satisfactory to it that the requisite number of noteholders party to the Note Purchase Agreement have duly executed and delivered an agreement to substantially the same effect as this waiver agreement such that no default, event of default or unmatured default would exist under the Note Agreement during the Waiver Period. Furthermore, the parties hereto agree that from and after the date hereof until the earlier of the end of the Waiver Period and the date of delivery to the Administrative Agent and the Lenders of the financial statements which are the subject of the Specified Defaults, for purposes of calculating the Applicable Floating Rate Margin, Applicable Eurodollar Margin, Applicable L/C Fee Percentage and Applicable Commitment Fee Percentage under Section 2.14(D)(ii), the Leverage Ratio shall be determined based upon the Unaudited Statements.

          Pursuant to the provisions of Section 9.3 of the Credit Agreement, (a) no delay or omission of the Lenders or the Administrative Agent to exercise any right under the Loan Documents shall impair such right or be construed to be a waiver of any Default or Unmatured Default or an acquiescence therein, and the making of a Loan or the issuance of a Letter of Credit notwithstanding the existence of a Default or the inability of the Company or any other Borrower to satisfy the conditions precedent to such Loan or issuance of such Letter of Credit shall not constitute any waiver or acquiescence and (b) any single or partial exercise of any such right shall not preclude other or further exercise thereof or the exercise of any other right, and no waiver, amendment or other variation of the terms, conditions or provisions of the Loan Documents whatsoever shall be valid unless in writing signed by the requisite number of Lenders required pursuant to Section 9.2, and then only to the extent in such writing specifically set forth. All remedies contained in the Loan Documents or by law as a result of the Specified Defaults are hereby reserved on behalf of the Administrative Agent and the Lenders following the Waiver Period.

          2. Conditions of Effectiveness. This Waiver shall be deemed to have become effective as of the date hereof, but such effectiveness shall be subject to the following conditions: (a) the Administrative Agent shall have received (i) executed counterparts of this Waiver duly executed and delivered by the Company, the Subsidiary Borrowers and the Required Lenders and executed counterparts of the Reaffirmation attached hereto duly executed

and delivered by the Subsidiary Guarantors and (ii) the Unaudited Statements and (b) the Company shall fail to (i) file with the Commission its financial results and related documents for the third and fourth quarters of its 2005 fiscal year and for its 2005 fiscal year and (ii) deliver to the Administrative Agent and the Lenders the financial reports and related documents required under the Credit Agreement for such periods.

          3. Representation and Warranties. Each Borrower hereby represents and warrants that, other than in connection with the Specified Defaults, (i) all of the representations and warranties contained in Article VI of the Credit Agreement are true and correct and (ii) no Default or Unmatured Default is in effect.

          5. No Implicit Waiver. Except as expressly set forth herein in connection with the Specified Defaults, (i) the execution, delivery and effectiveness of this Waiver shall neither operate as a waiver of any rights, power or remedy of the Administrative Agent or the Lenders under the Credit Agreement or any other documents executed in connection with the Credit Agreement, nor constitute a waiver of any provision of the Credit Agreement nor any other document executed in connection therewith and (ii) the Credit Agreement shall remain in full force and effect in accordance with their original terms.

          6. GOVERNING LAW. THE ADMINISTRATIVE AGENT ACCEPTS THIS WAIVER NO. 2, ON BEHALF OF ITSELF AND THE LENDERS, AT CHICAGO, ILLINOIS BY ACKNOWLEDGING AND AGREEING TO IT THERE. ANY DISPUTE BETWEEN ANY BORROWER AND THE ADMINISTRATIVE AGENT OR ANY LENDER ARISING OUT OF, CONNECTED WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED BETWEEN THEM IN CONNECTION WITH, THIS WAIVER, THE CREDIT AGREEMENT OR ANY OF THE OTHER LOAN DOCUMENTS, AND WHETHER ARISING IN CONTRACT, TORT, EQUITY, OR OTHERWISE, SHALL BE RESOLVED IN ACCORDANCE WITH THE INTERNAL LAWS (INCLUDING §735 ILCS 105/5-1 ET SEQ. BUT OTHERWISE WITHOUT REGARD TO THE CONFLICTS OF LAWS PROVISIONS) OF THE STATE OF ILLINOIS.

[Signature Pages Follow]

     IN WITNESS WHEREOF, this Waiver No. 3 has been duly executed as of the day and year first above written.

CHICAGO BRIDGE & IRON COMPANY N.V., as the Company
By:	/s/ Walter G. Browning
Name: Walter G. Browning
Title: Authorized Signer

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

CB&I CONSTRUCTORS, INC., as a Subsidiary Borrower
By: Name:	/s/ Luciano Reyes Luciano Reyes
Title:	Vice President and Treasurer
CBI SERVICES, INC., as a Subsidiary Borrower
By: Name:	/s/ Terrence G. Browne Terrence G. Browne
Title:	Treasurer
CHICAGO BRIDGE & IRON COMPANY (DELAWARE), as a Subsidiary Borrower
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer
CB&I TYLER COMPANY, as a Subsidiary Borrower
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Treasurer
CHICAGO BRIDGE & IRON COMPANY B.V., as a Subsidiary Borrower
By:	/s/ Walter G. Browning
Name:	Walter G. Browning
Title:	Managing Director

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

JPMORGAN CHASE BANK, N.A. (successor by merger to Bank One, NA), as Administrative Agent and as a Lender
By:	/s/ James R. Dolphin
Name:	James R. Dolphin
Title:	Vice President
BANK OF AMERICA, N.A., as Syndication Agent and as a Lender
By:	/s/ Robert W. Troutman
Name:	Robert W. Troutman
Title:	Managing Director
BANK OF MONTREAL, as a Documentation Agent and as a Lender
By:	/s/ Joann L. Holman
Name:	Joann L. Holman
Title:	Director
WELLS FARGO BANK, N.A., as a Documentation Agent and as a Lender
By:
Name:
Title:

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

BNP PARIBAS, as a Documentation Agent and as a Lender
By:	/s/ Jamie Dillon
Name:	Jamie Dillon
Title:	Managing Director
By:	/s/ Sandy Bertram
Name:	Sandy Bertram
Title:	Vice President
THE ROYAL BANK OF SCOTLAND plc , as a Documentation Agent and as a Lender
By:	/s/Paul McDonagh
Name:	Paul McDonagh
Title:	Managing Director
FORTIS CAPITAL CORP., as a Lender
By:	/s/ Douglas Riahi
Name:	Douglas Riahi
Title:	Managing Director
By:	/s/ Steven Silverstein
Name:	Steven Silverstein
Title:	Vice President
CREDIT SUISSE, Cayman Islands Branch, as a Lender
By:	/s/ Thomas R. Cantello
Name:	Thomas R. Cantello
Title:	Vice President
By:	/s/ Gregory S. Richards
Name:	Gregory S. Richards
Title:	Associate

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

BARCLAYS BANK plc, as a Lender

By:

Name:

Title:

CALYON NEW YORK BRANCH, as a Lender
By:	/s/ Michael Willis
Name:	Michael Willis
Title:	Vice President
By:	/s/ Page Dillehunt
Name:	Page Dillehunt
Title:	Managing Director

UBS LOAN FINANCE LLC, as a Lender
By:	/s/ Pamela Oh
Name:	Pamela Oh
Title:	Associate Director, Banking Products Services, US
By:	/s/ Joselin Fernandes
Name:	Joselin Fernandes
Title:	Associate Director, Banking Products Services, US
PNC BANK, NATIONAL ASSOCIATION, as a Lender
By:	/s/ W. J. Bowne
Name:	W. J. Bowne
Title:	Managing Director

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

REGIONS BANK, as a Lender
By:	/s/ Keith S. Page
Name:	Keith S. Page
Title:	Senior Vice President
ALLIED IRISH BANK, PLC, as a Lender
By:
Name:
Title:
By:
Name:
Title:
THE NORTHERN TRUST COMPANY, as a Lender
By:	/s/ Cory Schuster
Name:	Cory Schuster
Title:	Commercial Banking Officer
STANDARD CHARTERED BANK, as a Lender
By:	/s/ Frieda Youlios
Name:	Frieda Youlios
Title:	Vice President
By:	/s/ Robert K. Reddington
Name:	Robert K. Reddington
Title:	AVP/Credit Documentation, Credit Risk Control, Standard Chartered Bank N.Y.

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

ABU DHABI INTERNATIONAL BANK INC, as a Lender
By:	/s/ Nagy S. Kolta
Name:	Nagy S. Kolta
Title:	Executive Vice President
By:	/s/ Pamela Sigda
Name:	Pamela Sigda
Title:	Senior Vice President
AMEGY BANK NATIONAL ASSOCIATION, as a Lender
By:	/s/ Jill S. Vaughan
Name:	Jill S. Vaughan
Title:	Senior Vice President
BANK OF NEW YORK, as a Lender
By:	/s/ Kevin Higgins
Name:	Kevin Higgins
Title:	Vice President
HIBERNIA NATIONAL BANK, as a Lender
By:	/s/ Lane Naley
Name:	Lane Naley
Title:	Senior Vice President
WOODFOREST NATIONAL BANK, as a Lender
By:
Name:
Title:

Signature Page to Waiver No. 3 to
Chicago Bridge & Iron Company N.V. et al
Amended and Restated Credit Agreement dated as of May 12, 2005

REAFFIRMATION

     Each of the undersigned hereby acknowledges receipt of a copy of the foregoing Waiver No. 3 in connection with that certain Amended and Restated Credit Agreement dated as of May 12, 2005 (as the same may be amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”) by and among Chicago Bridge and Iron Company N.V. (the “Company”), certain Subsidiaries of the Company party thereto as Borrowers (the “Subsidiary Borrowers”), JPMorgan Chase Bank, N.A. (successor by merger to Bank One, NA) as Administrative Agent (the “Administrative Agent”) under the Credit Agreement and the lenders party to said Credit Agreement, which Waiver No. 3 is dated as of March 30, 2006 (the “Waiver”). Capitalized terms used in this Reaffirmation and not defined herein shall have the meanings given to them in the Credit Agreement. Without in any way establishing a course of dealing by the Administrative Agent or any Lender, each of the undersigned consents to the Waiver and reaffirms the terms and conditions of the Guaranty and any other Loan Document executed by it and acknowledges and agrees that such agreement and each and every such Loan Document executed by the undersigned in connection with the Credit Agreement remains in full force and effect and is hereby reaffirmed, ratified and confirmed. All references to the Credit Agreement contained in the above-referenced documents shall be a reference to the Credit Agreement as so modified by the Waiver and as the same may from time to time hereafter be amended, modified or restated.

[signature pages follow]

CHICAGO BRIDGE & IRON COMPANY N.V.
By: CHICAGO BRIDGE & IRON COMPANY B.V.
Its: Managing Director
By:	/s/ Walter G. Browning
Name:	Walter G. Browning
Title:	Authorized Signer
CHICAGO BRIDGE & IRON COMPANY
a Delaware corporation
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer
CHICAGO BRIDGE & IRON COMPANY (DELAWARE)
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer
CB&I TYLER COMPANY
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Treasurer
CB&I CONSTRUCTORS, INC.
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer

CBI SERVICES, INC.
By:	/s/ Terrence G. Browne
Name:	Terrence G. Browne
Title:	Treasurer
CHICAGO BRIDGE & IRON COMPANY
an Illinois corporation
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer
HORTON CBI, LIMITED
By:	/s/ Mark A. Stobart
Name:	Mark A. Stobart
Title:	Vice President, Sales
CBI VENEZOLANA, S.A.
By:	/s/ Orlando Gomes
Name:	Orlando Gomes
Title:	Treasurer
CBI EASTERN ANSTALT
By:	/s/ Alan R. Black
Name:	Alan R. Black
Title:	Director

CBI CONSTRUCTORS PTY, LTD.
By:	/s/ Ross Adame
Name:	Ross Adame
Title:	Director
LEALAND FINANCE COMPANY B.V.
By:	/s/ Peter K. Bennett
Name:	Peter K. Bennett
Title:	Managing Director
CB&I (EUROPE) B.V.
By:	/s/ Alan R. Black
Name:	Alan R. Black
Title:	Director
ARABIAN GULF MATERIAL SUPPLY COMPANY, LTD.
By:	/s/ Harold Paul Mercer
Name:	Harold P. Mercer
Title:	Director
ASIA PACIFIC SUPPLY CO.
By:	/s/ Timothy J. Moran
Name:	Timothy J. Moran
Title:	Treasurer
CBI COMPANY LTD.
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Treasurer

CBI CONSTRUCCIONES S.A.
By:	/s/ Jose Manuel Tappata
Name:	Jose Manuel Tappata
Title:	Director
CBI CONSTRUCTORS LIMITED
By:	/s/ Peter K. Bennett
Name:	Peter K. Bennett
Title:	Director
CBI HOLDINGS (U.K.) LIMITED
By:	/s/ Timothy J. Moran
Name:	Timothy J. Moran
Title:	Director
CBI OVERSEAS, LLC
By:	/s/ Peter Han
Name:	Peter Han
Title:	Group Vice President
CENTRAL TRADING COMPANY, LTD.
By:	/s/ Luciano Reyes
Name:	Luciano Reyes
Title:	Vice President and Treasurer
CHICAGO BRIDGE & IRON (ANTILLES) N.V.
By:	/s/ Walter G. Browning
Name:	Walter G. Browning
Title:	Managing Director

CHICAGO BRIDGE & IRON COMPANY B.V.
By:	/s/ Walter G. Browning
Name:	Walter G. Browning
Title:	Managing Director
CMP HOLDINGS B.V.
By:	/s/ Alan R. Black
Name:	Alan R. Black
Title:	Director
PACIFIC RIM MATERIAL SUPPLY COMPANY, LTD.
By:	/s/ Harold Paul Mercer
Name:	Harold Paul Mercer
Title:	Director
HOWE-BAKER INTERNATIONAL, L.L.C.
By:	/s/ Luke V. Scorsone
Name:	Luke V. Scorsone
Title:	President
HOWE-BAKER ENGINEERS, LTD.
By and through its General Partner,
Howe-Baker Management, L.L.C.
By:	/s/ Luke V. Scorsone
Name:	Luke V. Scorsone
Title:	President
HOWE-BAKER HOLDINGS, L.L.C.
By:	/s/ Luke V. Scorsone
Name:	Luke V. Scorsone
Title:	President

HOWE-BAKER MANAGEMENT, L.L.C.
By:	/s/ Luke V. Scorsone
Name: Luke V. Scorsone
Title: President
HBI HOLDINGS, L.L.C.
By:	/s/ Luke V. Scorsone
Name: Luke V. Scorsone
Title: President
CONSTRUCTORS INTERNATIONAL, L.L.C.
By:	/s/ Luke V. Scorsone
Name: Luke V. Scorsone
Title: President
MATRIX ENGINEERING, LTD.
By:	/s/ Scott T. Baker
Name: Scott T. Baker
Title: President
HOWE-BAKER INTERNATIONAL MANAGEMENT, L.L.C.
By:	/s/ Scott T. Baker
Name: Scott T. Baker
Title: President
A&B BUILDERS, LTD.
By:	/s/ Scott T. Baker
Name: Scott T. Baker
Title: President

MATRIX MANAGEMENT SERVICES, L.L.C.
By:	/s/ Dennis C. Planic
Name: Dennis C. Planic
Title: Vice President — Finance, Treasurer and CFO
SOUTHERN TROPIC MATERIAL SUPPLY COMPANY, LTD.
By:	/s/ Alan R. Black
Name: Alan R. Black
Title: Treasurer

CB&I (NIGERIA) LIMITED
By:	/s/ Peter R. Rano
Name: Peter R. Rano
Title: Director
CHICAGO BRIDGE & IRON (ESPANA) S.A.
By:	/s/ Alan R. Black
Name: Alan R. Black
Title: Director
CBI (PHILLIPINES), INC.
By:	/s/ Alan R. Black
Name: Alan R. Black
Title: Treasurer
CB&I JOHN BROWN LIMITED
By:	/s/ Colin L. Astin
Name: Colin L. Astin
Title: Director

MORSE CONSTRUCTION GROUP, INC.
By:	/s/ Terrence G. Browne
Name: Terrence G. Browne
Title: Treasurer
CBI HUNGARY HOLDING LIMITED LIABILITY COMPANY
By:	/s/ Raymond Buckley
Name: Raymond Buckley
Title: Director
CBI LUXEMBOURG S.A.R.L.
By:	/s/ Timothy J. Moran
Name: Timothy J. Moran
Title: Managing Director
CB&I FINANCE COMPANY LIMITED
By:	/s/ Alan R. Black
Name: Alan R. Black
Title: Managing Director
CBI AMERICAS, LTD.
By:	/s/ Luciano Reyes
Name: Luciano Reyes
Title: Treasurer
CSA TRADING COMPANY, LTD.
By:	/s/ Luciano Reyes
Name: Luciano Reyes
Title: Treasurer

CB&I WOODLANDS L.L.C.
By:	/s/ Luciano Reyes
Name: Luciano Reyes
Title: Treasurer
WOODLANDS INTERNATIONAL INSURANCE COMPANY LIMITED
By:	/s/ Robert Havlick
Name: Robert Havlick
Title: Director