Named as the first African-American Brigadier General of the Army Nurse Corps in 1979, Hazel W. Johnson-Brown apparently reached the most honorable rank when she was appointed as the chief of the ANC. She then commanded 7,000 men and women in the Army National Guard and Army Reserves, and overseeing numerous medical centers, free-standing clinics, and community hospitals in Germany, Italy, Japan, Korea, Panama, and the United States. Hazel W. Johnson-Brown's military success started with apparent prejudice, when she was rejected of enrolment at the West Chester School of Nursing. This was the obstacle that she wanted to overcome. Hence, she went off for New York City in 1947, and was admitted in the Harlem Hospital School of Nursing. Her first professional work was at the Philadelphia Veteran's Hospital but enlisted into the Army Nurse Corps in 1955 with the encouragement of colleagues. Hazel swiftly rose from the ranks, accumulating impressive credentials from different positions she held, and finally got to the pinnacle of her career as Chief of ANC, with the rank of Brigadier General.

After enjoying success in the military service, Brig. Gen. Johnson-Brown retired from the army in 1983. She journeyed to her second career in academia as professor of nursing in Washington D.C.'s Georgetown University, and in Virginia's George Mason University as instrument to founding Centre for Health Policy. When she retired from teaching in 1997, Brig. Gen. Johnson-Brown serves different health administration boards in the Washington area.