It develops and offers services, technology and systems that specialize in treatment, purification, cleaning and hygiene of water in a wide variety of applications.

In 1984, Ecolab acquired pest elimination company Lystads, Inc., of Grand Forks, North Dakota.

[5] In 1986, the company changed its name from Economics Laboratory to Ecolab Inc. and was listed on the New York Stock Exchange.

[8][circular reference] In 2007, Ecolab acquired Microtek Medical Holdings, Inc., expanding its infection prevention expertise and offerings to hospitals and other healthcare facilities.

[9] In 2008, Henkel sold all of the 73 million shares, nearly a 29.5% stake it held in Ecolab, ending the two-decade-long partnership.

[6] In 2011, Ecolab announced a merger with Nalco Holding Company, Inc., an industrial water technology firm.

[30] In the same year, Ecolab acquired the assets of UltraClenz, a developer of electronic hand hygiene compliance monitoring systems and dispensers.

[34] In 2021, Ecolab acquired Purolite, a provider of ion-exchange resins for biopharmaceutical purification for approximately $3.7 billion.

[36] Ecolab helps organizations treat their water in industries including food, healthcare, hospitality, and manufacturing.