Exhibit 10.1

AMENDMENT NO. 1 TO THE

THREE YEAR REVOLVING CREDIT AGREEMENT

Dated as of August 26, 2011

AMENDMENT NO. 1 TO THE THREE YEAR REVOLVING CREDIT AGREEMENT (“ this Amendment ”) among KBR, INC., a Delaware corporation (the “ Borrower ”), the banks and other entities that are parties to the Credit Agreement referred to below (collectively, the “ Banks ”), Citibank, N.A., as a Bank and as Administrative Agent (the “ Administrative Agent ”) and the other Banks parties thereto.

PRELIMINARY STATEMENT: The Borrower, the Banks and the Administrative Agent have entered into a Three Year Revolving Credit Agreement dated as of November 3, 2009 (as amended, supplemented or otherwise modified through the date hereof, the “ Credit Agreement ”), and the Borrower and the Required Banks have agreed to amend the Credit Agreement as hereinafter set forth Capitalized terms not otherwise defined in this Amendment have the same meanings as specified in the Credit Agreement.

SECTION 1. Amendment to Credit Agreement . Section 5.02(g)(i) of the Credit Agreement is hereby amended by deleting each reference to “$400 million” and inserting in lieu thereof “$500 million”.

SECTION 2 Condition of Effectiveness. This Amendment shall become effective as of the date first above written when the Administrative Agent shall have received counterparts of this Amendment executed by the Borrower, the Subsidiary Guarantors and the Required Banks.

SECTION 3. Representations and Warranties of the Borrower . The Borrower represents and warrants that, both before and after giving effect to this Amendment: (i) the representations and warranties contained in each Loan Document are correct on and as of the date hereof (except that those representations and warranties that expressly relate to