8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

______________________

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): November 19, 2012

Sigma-Aldrich Corporation

(Exact name of registrant as specified in charter)

Delaware	000-08135	43-1050617
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

3050 Spruce Street, St. Louis, Missouri 63103

(Address of principal executive offices, including Zip Code)

Registrant’s telephone number, including area code: (314) 771-5765

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligations of the registrant under any of the following provisions (see General Instruction A.2.):

o    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Section 5 - Corporate Governance and Management

Item 5.02Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On November 19, 2012, Sigma-Aldrich Corporation (the "Company") announced an organizational realignment effective January 1, 2013. Pursuant to the realignment, the Company's Research business will be divided into two new business units - Applied Markets and Research Markets. Franklin D. Wicks, Executive Vice President and President, Research, will become President of the Applied Markets Business Unit. Dr. Wicks will remain an Executive Vice President of the Company. Eric M. Green, Vice President and Managing Director, International, will become President of the Research Markets Business Unit. Gilles A. Cottier, Executive Vice President and President, SAFC, will continue to lead the SAFC business, which will be renamed the SAFC Commercial Markets Business Unit.

For additional information regarding the organizational realignment, please see the corresponding press release announcing it. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Section 9 - Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits.

Exhibit No.	Description
99.1	Text of press release dated November 19, 2012.

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 hereunto duly authorized.

		SIGMA-ALDRICH CORPORATION
Date:	November 19, 2012	By	/s/ George L. Miller
			George L. Miller Senior Vice President, General Counsel and Secretary

Exhibit Index

Exhibit No.	Description
99.1	Text of press release dated November 19, 2012.

EX-99.1

3050 Spruce Street, St. Louis, MO 63103 USA

Tel: (800) 521-8956 (314) 771-5765 Fax: (800) 325-5052 (314) 771-5757

For questions, contact:

Quintin Lai

Vice President, Investor Relations

(314) 898-4643

FOR IMMEDIATE RELEASE - St. Louis, MO, November 19, 2012

SIGMA-ALDRICH ALIGNS INTO THREE NEW MARKET-FOCUSED BUSINESS UNITS

Effective January 1, 2013, Sigma-Aldrich Corporation (NASDAQ: SIAL) will align its organization into three market-focused business units that are defined by the customers and markets they serve. This new organization will enable Sigma-Aldrich to better address the needs of its global customers and to further drive global sales growth.

Frank Wicks will transition from his current role as President of the Research business to become President of the new Applied Markets Business Unit. This business unit will serve customers in Diagnostics, Testing and Industrial markets.

Eric Green will transition from his current role as Vice President and Managing Director of the International region (APLA) to become President of the newly structured Research Markets Business Unit. This business unit will focus on broadening the offering of research products to scientists in Life Science, Academic, Government and Hospital settings around the world. Eric will continue to have responsibility for the Latin America region as well.

Gilles Cottier will continue to lead the SAFC business. This business will be renamed the SAFC Commercial Markets Business Unit and will continue to serve customers in the Life Science and Electronic markets.

Gerrit van den Dool will transition from his current role as Managing Director of the North American region (United States and Canada) to become Managing Director of the European region (EMEA). Gerrit will relocate to St. Gallen, Switzerland. Jason Apter will transition from his role of Chief of Staff to become Managing Director of the Asia Pacific region and will relocate to Singapore. Customers in the North American region will be managed directly by the three business units - Applied Markets, Research Markets and SAFC Commercial Markets.

Sigma-Aldrich intends to provide more information about the structure, sales and growth prospects of each of the three business units early in 2013 in conjunction with its year-end financial results release.

About Sigma-Aldrich: Sigma-Aldrich is a leading Life Science and High Technology company whose biochemical and organic chemical products, kits and services are used in scientific research, including genomic and proteomic research, biotechnology, pharmaceutical development, the diagnosis of disease and as key components in pharmaceutical, diagnostics and high technology manufacturing. Sigma-Aldrich customers include more than one million scientists and technologists in life science companies, university and government institutions, hospitals and industry. The Company operates in 38 countries and has

approximately 9,000 employees whose objective is to provide excellent service worldwide. Sigma-Aldrich is committed to accelerating customer success through innovation and leadership in Life Science, High Technology and Service. For more information about Sigma-Aldrich, please visit its website, at www.sigma-aldrich.com.