The office secretary has been a fixture of American business for years. The person, usually a woman, was responsible for managing the office, running errands for the boss, typing, filing and fulfilling many other duties, including being what amounted to a personal assistant for the boss. They accounted for some 4.1 million jobs in 2004, according to the U.S. Department of Labor.

As technology has advanced, the duties of the secretary, often maligned, have changed. The term “administrative assistant” is much closer to the actual duties of one of these employees. The U.S. Department of Labor even has a entry about administrative assistants and described their duties: “Secretaries and administrative assistants are responsible for a variety of administrative and clerical duties necessary to run an organization efficiently. They serve as information and communication managers for an office; plan and schedule meetings and appointments; organize and maintain paper and electronic files; manage projects; conduct research; and disseminate information by using the telephone, mail services, Web sites, and e-mail. They also may handle travel and guest arrangements.” But any administrative assistant worth his or her salt will tell you this barely scratches the surface of everything they do.

The good administrative assistant knows intimately how the office functions. While all offices look the same on the surface, each office is different, often influenced by the industry it serves. Some have a more casual chain of command, some are very formal. The movie “The Devil Wears Prada” is a funny and revealing look at the world of the administrative assistant. How could Miranda Priestley have done all she did without her assistants keeping all the balls in the air?

In the office, the experienced administrative assistant knows, for instance, which faxes are important and which are trash; what snail mail can be safely discarded; which e-mails must be forwarded to the boss, and which he or she can deal with. The administrative assistant also deals with the public in many offices, and is a source of general information. He or she will also probably be responsible, at least in part, in training new office staff. She has to know how to work with a variety of office equipment, and may be experienced enough to do minor repairs.

If the administrative assistant is the boss’s primary assistant, she will probably type and compose part of her supervisor’s correspondence, take many of his calls and keep his appointments up to date. An administrative assistant is served best by a college degree, but a sharp high school graduate who is technologically savvy and has good writing skills could also do the job. He or she will need a thorough knowledge of a word processing program, and should know his way around a computer with confidence.

Management may flatter itself that the company couldn’t get along without it, but fire the administrative assistant, and watch how quickly the business falls apart.