Keeping scientists busy is VWR International's business. The company distributes more than 1,200,000 laboratory products used in a diversity of scientific research fields. Its vast supply ranges from chemicals to lab instruments to protective clothing, produced by major OEMs including Merck KGaA, Carl Zeiss, Kimberly Clark, and Welch Allyn. VWR's lineup is sold worldwide to more than 250,000 pharmaceutical and biotech customers, as well as industrial, governmental, and educational organizations. Other services include technical support, storeroom management, and supply chain systems integration. The company nets about half of its sales in North America. VWR operates as a subsidiary of Madison Dearborn Partners.