By 1936, Berrett began writing textbooks to be used in the LDS Church's schools and was an editor for the
Church Educational System's (CES) curriculum development. Berrett's most notable work was
The Restored Church, a text to teach the history of the LDS Church; the book went through at least 16 editions. He also compiled with Alma Burton
Readings in LDS Church History. In 1943, Berrett was appointed special prosecutor for the
Office of Price Administration for the Utah Division. In 1946, he became an assistant U.S. attorney in
Alaska Territory. He left government employment in 1947 and became a lawyer in private practice in
Salt Lake City. He also was on the editorial staff of the
Deseret News. From 1935 to 1953, Berrett was a member of the
Deseret Sunday School Union General Board. In 1947, Berrett joined the BYU faculty as a professor of Church History. In 1951, he was one of the key figures in getting an ROTC unit located at BYU. He also worked closely with
Ernest L. Wilkinson in recruiting more faculty to BYU. In 1953, Berrett was appointed vice president of both BYU and CES. From 1962 to 1965 Berrett served as chairman of the Utah Committee on Children and Youth. In 1965, the LDS Church's seminary and institute programs were separated from the BYU administration. Berrett was appointed head of seminaries, institutes and all church-run colleges and schools (other than BYU). In 1972, Berrett retired and worked on writing a three-volume history of CES. This was not published but was later re-worked into a one-volume history published in 1988 as
A Miracle in Week-day Religious Education. == Personal life ==