He was known primarily for his work in Ecuadorian and Andean archaeology and spent most of his career at the Field Museum of Natural History.
The primary focus of her work was with the Navajo and she served as the director of the Curriculum Study Project of the American Anthropological Association.
He performed archaeological survey work at Tsegie and Skeleton Mesa with the First Rainbow Bridge Monument Valley Exhibition.
His fieldwork in Andean archaeology got its start in 1937 when he worked with Peruvian archaeologist Julio C. Tello at the behest of prominent anthropologist Alfred L. Kroeber with whom Collier studied at UC Berkeley.
In 1946, he became a part of the Viru Valley Project “a cutting edge cooperative undertaking at the time, the results of which were to have a profound and long-enduring effect on the interpretation of Peruvian prehistory”.
[3]: 45 The research he did for the project, during which he undertook archaeological survey work with Gordon Willey, served as the basis for his Ph.D. dissertation.
The first, Mayan Art: Rubbings from Stone Carvings, involved the first use at the Field Museum of a projector with a synchronized tape lecture.
Most of the pieces in the exhibition were borrowed from a private collection in Guayaquil, Ecuador and focused on ceramics from Ecuadorian coastal prehistory.
[2] Inspired by the Indians Before Columbus exhibit, a book of the same name was published in 1947 by Collier, Paul Martin, and George Quimby.