Madison, WI, US (January 4, 2005) - SAFC, a member of the Sigma-Aldrich Group (NASDAQ:SIAL), has announced the appointment of Dr. Trevor Calkins as Director of Process Development for its SAFC Pharma business.

Heading a team of eight chemists and three analysts, Dr. Calkins will oversee SAFC Pharma's R&D projects from development through manufacture.

A chemistry graduate of Cornell College, Trevor went on to study for his PhD under Dr. Janet Wisnewski-Grissom at the University of Utah, before undertaking an NIH postdoctoral fellowship with Dr. Barry Trost at Stanford University.

On completion of his fellowship, Trevor joined Microcide Pharmaceuticals' Medicinal Chemistry Department, working on the discovery and development of methicillin potentiators and MRSA active cephalosporins. He then spent six years as a Process Research Chemist with the Eisai Research Institute, Andover MA, where he was Project Leader for internal campaigns and relationships with external Clinical Research Organisations before joining SAFC in 2005.

Matthew Hanson, Market Segment Manager for SAFC Pharma, comments, "Trevor's wealth of business experience gives him a unique insight into the development of customer relationships. He will work closely with the other SAFC divisions to fulfil our aim of making SAFC the world leader in pharmaceutical development services, and we welcome him to our team."

About SAFC:

SAFC is the custom manufacturing group within Sigma-Aldrich that focuses on both biochemical production and the manufacturing of complex, multi-step organic synthesis of APIs and key intermediates. SAFC has manufacturing facilities around the world dedicated to providing manufacturing services for companies requiring a reliable partner to produce their custom manufactured materials.

About Sigma-Aldrich:

Sigma-Aldrich is a leading Life Science and High Technology company. Our biochemical and organic chemical products and kits are used in scientific and genomic research, biotechnology, pharmaceutical development, the diagnosis of disease and as key components in pharmaceutical and other high technology manufacturing. We have customers in life science companies, university and government institutions, hospitals, and in industry. Over one million scientists and technologists use our products. Sigma-Aldrich operates in 34 countries and has over 6,000 employees providing excellent service worldwide. We are committed to the success of our Customers, Employees and Shareholders through leadership in Life Science, High Technology and Service.

Cautionary Statement:

This release contains forward-looking statements relating to future performance, goals, strategic actions and initiatives and similar intentions and beliefs and other statements regarding Sigma-Aldrich's expectations, goals, beliefs, intentions and the like regarding future sales, earnings and other matters. These statements involve assumptions regarding Company operations, investments and conditions in the markets the Company serves. Although the Company believes its expectations are based on reasonable assumptions, such statements are subject to risks and uncertainties, including, among others, certain economic, political and technological factors. Actual results could differ materially from those stated or implied in this news release, due to, but not limited to, such factors as (1) changes in pricing and the competitive environment, (2) other changes in the business environment in which the Company operates, (3) uncertainties surrounding government healthcare reform, (4) government regulations applicable to the business, (5) the impact of fluctuations in foreign currency exchange rates, and (6) the ability to retain customers, suppliers and employees. (7) the success of research and development activities and (8) the impact of acquisitions and success in integrating and obtaining projected results from the acquisitions. The Company does not undertake any obligation to update these forward-looking statements.