In addition to his career at Long Island University, Brier has taught ancient Egyptian at The New School and Egyptology at Webb Institute for many years.

He has investigated well-known mummies such as Tutankhamen, Ramses the Great, Vladimir Lenin, Eva Perón (more commonly known as Evita), and the Medici family.

In 1994 Brier and a colleague, Ronald Wade, director of the State Anatomy Board of Maryland, mummified a human cadaver using ancient Egyptian techniques which they noted was the first known effort in 2,000 years.

This research earned Brier the affectionate nickname "Mr. Mummy" and was also the subject of the National Geographic television special of the same name, which made him a household name.

In 1999, Brier gave a series of 48 specially-prepared lectures entitled "The History of Ancient Egypt" for The Teaching Company.