Air Products and Chemicals, Inc. is an American international corporation whose principal business is selling gases and chemicals for industrial uses. Air Products' headquarters is in Allentown, Pennsylvania, in the Lehigh Valley region of Pennsylvania, in the United States. Air Products is the Lehigh Valley's third largest employer, after Lehigh Valley Hospital and St. Luke's Hospital. Leonard P. Pool founded the company in 1940. Its French subsidiary, headquartered in Saint-Quentin-Fallavier, was the site of a terrorist attack on June 26, 2015.

On September 17, 2015 Air Products announced its intent to spin off its Materials Technologies business. This new stand alone company has been renamed Versum Materials.

Air Products serves customers in technology, energy, healthcare, food and industrial markets worldwide with atmospheric industrial gases (mainly oxygen, nitrogen, argon, hydrogen and carbon dioxide), process and specialty gases, performance materials and chemical intermediates.

Air Products produces semiconductor materials, refinery hydrogen, natural gas liquefaction (LNG) technology and equipment, epoxy additives, gas cabinets, advanced coatings and adhesives. It is also noted as addressing the hydrogen fuel cell economy through hydrogen fueling stations as well as its personal care chemicals business.

Air Products also provided the liquid hydrogen and liquid oxygen fuel for the Space Shuttle External Tank. Air Products has had a working relationship with NASA for 50 years and has supplied the liquid hydrogen used for every Space Shuttle launch and the Mercury and Apollo missions.

In 2013, Air Products' high purity BIP (built-in purifier) argon was used to determine a more accurate value for the Boltzmann Constant.

In 2010, Air Products was awarded the Rushlight Hydrogen and Fuel Cells industry award for the Series 10 hydrogen fuelling station. The Rushlight Awards celebrate the leading environmental technologies and innovations by organizations throughout the UK and Ireland. The purpose is to promote what is happening in the world of hydrogen and fuel cells to the public and enable further development and funding to be granted toward reducing carbon emissions.

On January 15, 2004, Air Products (NYSE: APD) was named a Maplecroft Climate Innovation Indexes (CIIs) Leader, ranking 17th out of the 300 largest U.S. companies evaluated for their climate-related innovation and carbon management programs. Air Products is currently working on several preeminent carbon capture and storage demonstration projects around the world.

Air Products was included on the Dow Jones Sustainability North America Index as one of the best performing sustainable companies for 2008/11. Only the top 94 percent of the 987 largest North American companies are ultimately selected for the DJSI North America Index.

In 2001, Air Products Received an Award of Merit from the WateReuse Association for Outstanding Water Conservation Efforts for conserving 62 million US gallons (230,000 m) of drinking water annually by converting to recycled water for the cooling process at the Santa Clara, California, manufacturing facility. The award was presented during the 25th Annual WateReuse Symposium. WRA recognizes projects that have advanced the acceptance of water reuse through education, sound science, and technology using reclamation, recycling, reuse, or desalination for the benefit of the public and the environment.

On March 4, 2010, Corporate Responsibility Magazine named Air Products to its 100 Best Corporate Citizens List.