Bess Truman referred to herself as a "nobody" but to her husband, President Harry S Truman, she was his "chief advisor." The President was proud to say that she was consulted on every major issue, calling her "a full partner in all my transactions" and "the boss who bosses the boss." The Trumans were childhood sweethearts who finally married after Harry returned from military service in World War I. After a failed business venture, Truman became active in politics, eventually becoming a U.S. Senator in 1934. Bess was not overjoyed when Harry became FDR's running mate. According to her daughter Margaret, Bess was worried about the demands of the Vice-Presidency, especially the lack of privacy.

As soon as she became First Lady, she discontinued Eleanor Roosevelt's practice of frequent press conferences. She appeared in public only when necessary and devoted herself to making the Executive Mansion a home. It was her off-hand comment about life in the White House being "so-so" which led to the realization that the venerable house was in serious structural trouble and needed considerable repair. The Trumans had to vacate the Mansion while it was virtually reconstructed.

Although Mrs. Truman was regarded as a gracious hostess, her reserved nature made her little-known to the public. She adopted no special causes and, unlike her predecessor Eleanor Roosevelt, she caused no undue controversy. When the Trumans returned to Independence, Missouri at the conclusion of their White House years, her old neighbors reported that she was as unspoiled as if she had never left. At the time of her death in 1982, she was 97, the longest-lived First Lady in U.S. history.