President Eyring was a second and first lieutenant and was stationed in Albuquerque, where he was the head of field command, Armed Forces, Special Weapons Project. He didn't serve the usual two-year mission. However, two weeks after his arrival in New Mexico, he was called as a district missionary in the Western States Mission, serving in that calling almost two years to the day.

While at Stanford, he held teaching and administrative assignments in production management, operations and systems analysis, organizational behavior and management of the total enterprise. He also served as a visiting fellow for a year at the Massachusetts Institute of Technology and was founder, director or officer of at least two companies in Sunnyvale, Calif.

A consultant to a wide range of private and public enterprises, he was called by the First Presidency to serve as president of Ricks College (now BYU-Idaho) in 1971, where he served for six years before becoming deputy commissioner of church education. He was later named commissioner, where he served until being sustained as first counselor in the Presiding Bishopric in 1985, then a member of the First Quorum of the Seventy in 1992, and then as an apostle on April 1, 1995, at age 61.

Just before his call to the First Presidency, President Eyring represented the church on highly public issues that involved some controversy. Recently, in Cedar City, he was the church spokesman in issuing an apology to descendants of those murdered 150 years ago in the Mountain Meadows Massacre. Some 120 non-Mormon immigrants traveling toward California were killed on the order of local church leaders who commanded an LDS militia.

Among his past local positions were high councilor, YMMIA president, bishop's counselor and bishop.