-June 1898, during the Spanish American War, Miss Hasson became a contract nurse with the U.S. Army, subsequently serving on the hospital ship Relief and in the Philippines.

-1901-She left the Army

-1905-07 she served as a nurse in Panama

-1908 When the Navy Nurse Corps was established Hasson became its first Superintendent, taking the oath of office on 18 August 1908. Under her leadership, 19 additional nurses were recruited and trained for Naval service during 1908.

-January, 1911 The Nurse Corps had grown to 85 trained nurses by the time Miss Hasson resigned as Superintendent

-June 1917, Esther Hasson became a U.S. Army Reserve Nurse and served in Europe during the First World War, including duty as Chief Nurse of two Army base hospitals

-June 1919 left active service

-March 8, 1942 Chief Nurse Esther V. Hasson died in Washington, D.C.

Esther Voorhees Hasson