Exhibit 10.1

FIFTH AMENDMENT TO CREDIT AGREEMENT

THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (this “Amendment”) is made and entered
into effective as of July 11, 2006 (the “Effective Date”), by and among
HELMERICH & PAYNE INTERNATIONAL DRILLING CO., a Delaware corporation (the
“Borrower”), HELMERICH & PAYNE, INC., a Delaware corporation (the “Parent”), and
BANK OF OKLAHOMA, NATIONAL ASSOCIATION, as Lender (in such capacity, the
“Lender”) and as Administrative Agent (in such capacity, the “Administrative
Agent”), with reference to the following:

RECITALS

A.            The Borrower, the Parent, the Lender and the Administrative Agent
are parties to that certain Credit Agreement dated July 16, 2002, as amended by
(i) that certain First Amendment to Credit Agreement dated July 15, 2003,
(ii) that certain Second Amendment to Credit Agreement dated May 4, 2004,
(iii) that certain Third Amendment to Credit Agreement dated as of July 13,
2004, and (iv) that certain Fourth Amendment to Credit Agreement dated as of
July 12, 2005 (the Credit Agreement, as amended by the First, Second, Third and
Fourth Amendments thereto, is hereinafter referred to as the “Credit
Agreement”). Capitalized terms used in this Amendment and not otherwise defined
herein have the respective meanings assigned to them in the Credit Agreement,
and the rules of construction set forth in the Credit Agreement shall also
govern the construction and interpretation of this Amendment.

B.            Pursuant to the Credit Agreement, the Lender established the
Facility in favor of the Borrower.

C.            The Borrower has requested that the Lender (i) extend the
Revolving Commitment Termination Date from July 11, 2006, to July 10, 2007 and
(ii) extend the Facility Maturity Date from June 30, 2008, to June 30, 2009.

D.            The Lender has agreed to the foregoing requests, subject to the
terms and conditions set forth in this Amendment.

NOW, THEREFORE, in consideration of the premises and the mutual covenants and
agreements herein contained, and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the parties hereby amend
the Credit Agreement as follows:

1.             EXTENSION OF THE FACILITY. As of the Effective Date:

(i)            the Revolving Commitment Termination Date is extended from
July 11, 2006, to July 10, 2007, and the definition of “Revolving Commitment
Termination Date” appearing in Section 1.1 of the Credit Agreement is amended in
its entirety to read as follows:

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“Revolving Commitment Termination Date” means July 10, 2007, or such later date
to which the Revolving Commitment Termination Date may be extended from time to
time pursuant to Section 2.5(c).

(ii)           the Facility Maturity Date is extended from June 30, 2008, to
June 30, 2009, and the definition of “Facility Maturity Date” appearing in
Section 1.1 of the Credit Agreement is amended in its entirety to read as
follows:

“Facility Maturity Date” means June 30, 2009, or such later date to which the
Facility Maturity Date may be extended from time to time pursuant to
Section 2.5(c).

2.             WAIVER.

A.            Sections 7.1(a) and 7.1(b) of the Credit Agreement. For as long as
annual and quarterly financial statements that comply with the requirements of
Section 7.1(a) and Section 7.1(b) of the Credit Agreement are available to the
Lenders through publicly-available sources within the time periods required by
the Credit Agreement, the Borrower shall be deemed to have satisfied the
requirements of Section 7.1(a) and Section 7.1(b) of the Credit Agreement
(relating to annual and quarterly financial statements); provided, however, that
(i) the Borrower shall furnish a copy of the auditor’s opinion prepared in
connection with the audit of the Borrower’s annual financial statements,
(ii) the Borrower agrees to discuss with the Administrative Agent or its
representatives all such financial statements made available pursuant to
publicly-available sources, and (iii) the Administrative Agent reserves the
right to require the Borrower to submit financial statements in conformity with
all of the requirements of the Credit Agreement upon request by the
Administrative Agent.

B.            Sections 7.1(d) of the Credit Agreement. The Borrower shall not be
required to furnish copies of any report or “management letter” described in
Section 7.1(d) of the Credit Agreement to the Administrative Agent; provided,
however, that (i) the Borrower shall furnish a copy of any report or “management
letter” that contains any disclosure or footnote that will have (or is
reasonably likely to have) a Material Adverse Effect, and (ii) the
Administrative Agent reserves the right at any time to reinstate the
requirements of Section 7.1(d) of the Credit Agreement or to require the
Borrower to submit any specific report or “management letter” in conformity with
all of the requirements of the Credit Agreement upon request by the
Administrative Agent.

C.            Sections 7.1(e) of the Credit Agreement. For as long as the
filings, registrations, reports, statements and notices described in
Section 7.1(e) of the Credit Agreement are available to the Lenders through
publicly-available sources, the Borrower shall not be required to furnish copies
of the same to the Lenders; provided, however, that (i) the Borrower shall
furnish the Administrative Agent a copy of each proxy statement and Form 8-K
filed with the SEC, and (ii) the Administrative Agent reserves the right to
require the Borrower to submit filings, registrations, reports, statements and
notices in conformity with all of the requirements of the Credit Agreement upon
request by the Administrative Agent.

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3.             CONDITIONS PRECEDENT. The modifications to the Credit Agreement
set forth in this Amendment shall be effective from and after the Effective
Date, but only when each of the following conditions precedent shall have been
satisfied:

A.            Execution of Documents. This Amendment and such other documents or
instruments as may be contemplated by this Amendment or as may be reasonably
necessary to effectuate the intent and purposes of this Amendment shall have
been duly and validly authorized and executed by the parties thereto and
delivered to the Administrative Agent, all in form and substance satisfactory to
the Lender.

B.            No Defaults. There shall not have occurred or be continuing any
Default or Event of Default.

C.            Legal Matters. All legal matters incident to this Amendment and
the transactions contemplated hereby shall be satisfactory to the Administrative
Agent and the Lender.

4.             REPRESENTATIONS AND WARRANTIES. The Borrower and the Parent
confirm that, to the best of their knowledge, all representations and warranties
made by each of the Borrower and the Parent for themselves or on behalf of a
Credit Party in Article VI of the Credit Agreement are and will be true and
correct in all material respects on the Effective Date (with the dates appearing
in the first sentence of Section 6.5 thereof being changed to read September 30,
2003, September 30, 2004, September 30, 2005, and March 31, 2006, respectively,
and the date appearing in the final sentence of Section 6.5 thereof being
changed to read September 30, 2005), except that:

(i)            the representations and warranties set forth in Sections 2.6(a),
6.12(ii), 6.13(d), 6.14 and 7.6, respectively, of the Credit Agreement are
subject to the matters set forth in Schedules 2.6(a), 6.12(ii), 6.13(d), 6.14
and 7.6, respectively, attached hereto; and

(ii)           all of the representations and warranties set forth in the Credit
Agreement are subject to the fact that the spin-off of Cimarex Energy Co. and
related entities was consummated on September 30, 2002.

As used in this Paragraph 4, the phrase “to the best of their knowledge” means
the current, actual personal knowledge of the Executive Officers of the Borrower
and the Parent, without any undertaking by any of such Executive Officers to
conduct any inquiry for purposes of this Amendment.

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5.             GENERAL.

A.            Effect of Amendment. The terms of this Amendment shall be
incorporated into and form a part of the Credit Agreement. Except as amended,
modified and supplemented by this Amendment, the Credit Agreement shall continue
in full force and effect in accordance with its original stated terms, all of
which are hereby reaffirmed in every respect as of the date hereof. In the event
of any irreconcilable inconsistency between the terms of this Amendment and the
terms of the Credit Agreement or any other Credit Document, the terms of this
Amendment shall control and govern, and the agreements shall be interpreted so
as to carry out and give full effect to the intent of this Amendment. All
references to the “Credit Agreement” appearing in any of the Credit Documents
shall hereafter be deemed references to the Credit Agreement as amended,
modified and supplemented by this Amendment. The Borrower and the Parent each
hereby reaffirm all Credit Documents to which it is a party, and acknowledge
that such Credit Documents will continue in full force and effect, unabated and
uninterrupted, and will remain its valid and binding obligations, enforceable in
accordance with their terms.

B.            Schedules. Schedules 2.6(a), 6.12(ii), 6.14 and 7.6 attached
hereto are hereby substituted for the corresponding schedules to the Credit
Agreement.

C.            No Course of Dealing. This Amendment shall not establish a course
of dealing or be construed as evidence of any willingness on the Lender’s part
to grant other or future extensions or modifications, should any be requested.

D.            Descriptive Headings. The descriptive headings of the several
sections of this Amendment are inserted for convenience only and shall not be
used in the construction of the content of this Amendment.

E.             Governing Law. This Amendment shall be construed and enforced in
accordance with, and the rights of the parties shall be governed by, the laws of
the State of Oklahoma.

F.             Reimbursement of Expenses. The Borrower and the Parent agree,
jointly and severally, to pay the reasonable fees and out-of-pocket expenses of
Crowe & Dunlevy, counsel to the Administrative Agent, incurred in connection
with the preparation of this Amendment and the consummation of the transactions
contemplated hereby and thereby.

G.            Counterpart Execution. This Amendment may be executed in multiple
counterparts, each of which shall be deemed an original hereof and all of which
shall be but one and the same original instrument.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK.
SIGNATURE PAGE TO FOLLOW.]

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IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart of this
Amendment to be duly executed and delivered as of the date first above written,
effective as of the Effective Date.

BORROWER:

 

HELMERICH & PAYNE INTERNATIONAL

 

 

DRILLING CO.,

 

 

a Delaware corporation

 

 

 

 

 

 

 

 

 

 

 

 

By:

/s/ Douglas E. Fears

 

 

 

Name:

Douglas E. Fears

 

 

 

Title:

Executive Vice President

 

PARENT:

 

HELMERICH & PAYNE, INC.,

 

 

a Delaware corporation

 

 

 

 

 

 

 

 

 

 

 

 

By:

/s/ Douglas E. Fears

 

 

 

Name:

Douglas E. Fears

 

 

 

Title:

Vice President

 

ADMINISTRATIVE AGENT:

 

BANK OF OKLAHOMA, NATIONAL

 

 

ASSOCIATION

 

 

 

 

 

 

 

 

 

 

 

 

By:

/s/ Patrick R. Roberts

 

 

 

Name:

Patrick R. Roberts

 

 

 

Title:

Commercial Lending Officer

 

LENDER:

 

BANK OF OKLAHOMA, NATIONAL

 

 

ASSOCIATION

 

 

 

 

 

 

 

 

 

 

 

 

By:

/s/ Patrick R. Roberts

 

 

 

Name:

Patrick R. Roberts

 

 

 

Title:

Commercial Lending Officer

 

Revolving Commitment:

$50,000,000

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