Betty Olsen

As a provincial capital, Buôn Ma Thuột was one of the targets of the Tet Offensive in January 1968. The missionary compound was bombed and eventually overrun and eight of the thirteen missionaries were killed or died later in captivity. Olson endured ten months in captivity, with forced day-long marches, beatings, inadequate food, and no medical attention. Fellow captive agricultural aid worker Michael Benge recalled Olson's death on September 26, 1968:

In 1963, she again decided on missionary work and successfully applied to the Christian and Missionary Alliance. The next year, she trained in a Hong Kong leprosarium in preparation for work in Vietnam during the Vietnam War. She wrote "Most of the people that I have told about going to Vietnam are greatly concerned, and I appreciate this; however, I am not concerned, and I am very much at peace. I know that I may never come back, but I know that I am in the center of the Lord's will and Vietnam is the place for me."

Oslen trained as a nurse at Brooklyn Methodist Hospital from 1953 to 1956. She worked as an obstetrics nurse at Nyack Hospital while attending Nyack Missionary College in Nyack, New York. She graduated in 1962 with a major in missions. However, she wavered about her desire to do missionary work, writing "I remember saying to the Lord at this time that if this is all there is to the Christian life, then I don't want it." For a time she stayed with her parents while they were in Seattle, then went to Chicago and worked as an obstetrics nurse at West Suburban Hospital.

Betty Ann Olsen (October 22, 1934 – September 26, 1968) was an African-born American nurse and missionary. She was killed while captive as a prisoner of war by the North Vietnamese Army during the Vietnam War.

Betty Olsen was born on October 22, 1934, in Bouaké, French West Africa, present-day Côte d'Ivoire, one of two daughters of missionaries Walter Olsen and Elizabeth Olson, serving with the Christian and Missionary Alliance. She attended a missionary kids school some distance from her parents for her primary schooling. For high school, she attended the Hampden-Dubois Academy in Mount Dora, Florida, then a boarding school which often served the children of missionaries. While at the academy she decided to dedicate her life to being a missionary.