The American Type Culture Collection, which is also known as the ATCC, is a not-for-profit bioscience organization that maintains the world's largest and most diverse collection of microbiological life. Many laboratories and institutions maintain their own stockpile of microorganisms, usually those that are in frequent use in the facility. Some large culture collections are housed and maintained, usually by universities or private enterprises. But none of these rivals the ATCC in terms of size.

The ATCC collection includes repositories of bacterial species, animal viruses, cell lines (which are important for the growth of certain types of viruses), fungi, plant viruses, protists (microscopic organisms that have a nucleus that is contained within a membrane), and yeasts. As well, in conjunction with researchers at George Mason University, which borders the ATCC facility, research in areas such as bioinformatics is carried out.

The ATCC was founded, and continues to function, to acquire, confirm the identity of, preserve and distribute biological materials to scientists worldwide. Since its inception, the mandate has expanded to now include information technology and intellectual property. Today, in addition to offering the microbiological organisms for sale, the ATCC offers technical services and educational programs to academic, government, and private organizations.

The genesis of the ATCC began in 1921. Then, the Army Medical Museum accepted a then renowned culture collection called the Winslow Culture Collection. The collection was put under the care of the Washington, D.C. members of the Society of American Bacteriologists (in time, this society grew in scope and membership to become the American Society for Microbiology). In 1925, the ATCC became an official entity with its incorporation. The burgeoning culture collection was moved to the McCormick Institute in Chicago. Twelve years later the collection returned to Washington. Space was leased to house the collection. Over the years the increasing diversification of the ATCC and the acquisition of more cultures taxed the space, so a series of moves to larger and larger sites occurred. Finally, in 1998, the organization moved to the state-of-the-art facility it continues to occupy.

The present facility is 106,000 square feet in size and has almost 35,000 square feet of laboratory space, including specialized containment facilities for more hazardous house microorganisms. Over fifty ultra-low temperature freezers are used for the long-term storage of samples. Such storage avoids changes in the organisms that could result from storage at refrigeration temperatures.