UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q/A

AMENDMENT No. 1

(Mark One)

x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended December 2, 2006

OR

¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from              to             

Commission File Number: 0-12853

ELECTRO SCIENTIFIC INDUSTRIES, INC.

Oregon	93-0370304
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
13900 N.W. Science Park Drive, Portland, Oregon	97229
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number: (503) 641-4141

Registrant’s web address: www.esi.com

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).    Yes  x    No  ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

The number of shares outstanding of the Registrant’s Common Stock at January 2, 2007 was 29,156,689 shares.

EXPLANATORY NOTE

The cover page of the Quarterly Report on Form 10-Q for the three- and six-month periods ended December 2, 2006 filed by Electro Scientific Industries, Inc. (the “Company”) with the Securities and Exchange Commission on January 5, 2007 incorrectly stated the number of outstanding shares of the Company’s common stock. The correct number of such outstanding shares as of January 2, 2007 was 29,156,689, as reflected on the cover page to this Amendment No. 1 to Quarterly Report on Form 10-Q/A.

Except as identified in the immediately preceding paragraph, no other items included in the original Form 10-Q have been amended, and such items remain in effect as of the filing date of the original Form 10-Q. Additionally, this Amendment No. 1 to Quarterly Report on Form 10-Q/A does not purport to provide an update or a discussion of any other developments subsequent to the original Form 10-Q.

Item 6. Exhibits

This list is intended to constitute the exhibit index.

31.1 Certification of the Chief Executive Officer pursuant to Section 302(a) of the Sarbanes-Oxley Act of 2002.

31.2 Certification of the Chief Financial Officer pursuant to Section 302(a) of the Sarbanes-Oxley Act of 2002.

32.1 Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

32.2 Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Dated: January 5, 2007	ELECTRO SCIENTIFIC INDUSTRIES, INC.
	By	/s/ Nicholas Konidaris
		Nicholas Konidaris
		President and Chief Executive Officer
		(Principal Executive Officer)
	By	/s/ John Metcalf
		John Metcalf
		Senior Vice President of Administration,
		Chief Financial Officer and Corporate Secretary
		(Principal Financial Officer)
	By	/s/ Kerry Mustoe
		Kerry Mustoe
		Corporate Controller and Chief
		Accounting Officer
		(Principal Accounting Officer)

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