Throughout his career, and most notably with his 1991 address to the Linguistic Society of America, Krauss focused awareness of the global problem of endangered languages.

In fact, while en route to Alaska he visited Harry Hoijer, the leading scholar of Athabaskan languages at the time.

This turned out to be quite fortuitous for scholars of Athabaskan comparative linguistics, as Lower Tanana nicely demonstrated a split in the Proto-Athabaskan *ts- series which was not evidenced in Hoijer's data.

However, Eyak proved to be a crucial missing link for historical linguistics, being equally closely related to neighboring Ahtna and to distant Navajo.

With good Eyak data it became possible to establish the existence of the Athabaskan–Eyak–Tlingit language family, though phonological evidence for links to Haida remained elusive.

In his lecture, titled "The world's languages in crisis," Dr. Krauss famously warned:[4]"Obviously we must do some serious rethinking of our priorities, lest linguistics go down in history as the only science that presided obliviously over the disappearance of 90% of the very field to which it is dedicated."